test: Fix for a few data races

[paul1r]

What this PR does / why we need it:
Two different races addressed in this PR.

go test . -race -count=50 -run Test_ExitEarly -v   
=== RUN   Test_ExitEarly
--- PASS: Test_ExitEarly (0.00s)
=== RUN   Test_ExitEarly
==================
WARNING: DATA RACE
Write at 0x00c00064e508 by goroutine 115:
  github.com/grafana/loki/pkg/querier/queryrange.Test_ExitEarly.func1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval_test.go:1779 +0xb4
  github.com/grafana/loki/pkg/querier/queryrange/queryrangebase.HandlerFunc.Do()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/queryrangebase/roundtrip.go:80 +0x50
  github.com/grafana/loki/pkg/querier/queryrange.(*seriesLimiter).Do()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/limits.go:415 +0x7c
  github.com/grafana/loki/pkg/querier/queryrange.(*splitByInterval).loop()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval.go:162 +0x114
  github.com/grafana/loki/pkg/querier/queryrange.(*splitByInterval).Process.func1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval.go:126 +0x70

Previous read at 0x00c00064e508 by goroutine 113:
  github.com/grafana/loki/pkg/querier/queryrange.Test_ExitEarly()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval_test.go:1855 +0x940
  testing.tRunner()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1595 +0x1b0
  testing.(*T).Run.func1()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1648 +0x40

Goroutine 115 (running) created at:
  github.com/grafana/loki/pkg/querier/queryrange.(*splitByInterval).Process()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval.go:126 +0x140
  github.com/grafana/loki/pkg/querier/queryrange.(*splitByInterval).Do()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval.go:244 +0xb20
  github.com/grafana/loki/pkg/querier/queryrange.Test_ExitEarly()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/queryrange/split_by_interval_test.go:1853 +0x910
  testing.tRunner()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1595 +0x1b0
  testing.(*T).Run.func1()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1648 +0x40

Goroutine 113 (finished) created at:
  testing.(*T).Run()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1648 +0x5e8
  testing.runTests.func1()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:2054 +0x80
  testing.tRunner()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1595 +0x1b0
  testing.runTests()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:2052 +0x6e4
  testing.(*M).Run()
      /opt/homebrew/Cellar/go/1.21.6/libexec/src/testing/testing.go:1925 +0x9ec
  main.main()
      _testmain.go:273 +0x294
==================

after fix:

go test . -race -count=50 -run Test_ExitEarly
PASS
ok  	github.com/grafana/loki/pkg/querier/queryrange	1.778s

and

go test -count=10 -race . -run earlyExitOnQuorum
==================
WARNING: DATA RACE
Read at 0x00c00073a248 by goroutine 120:
  github.com/grafana/loki/pkg/querier.TestIngesterQuerier_earlyExitOnQuorum.func5.1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/ingester_querier_test.go:91 +0x128
  github.com/stretchr/testify/mock.(*Mock).MethodCalled()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/stretchr/testify/mock/mock.go:552 +0xd3c
  github.com/stretchr/testify/mock.(*Mock).Called()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/stretchr/testify/mock/mock.go:464 +0x140
  github.com/grafana/loki/pkg/querier.(*querierClientMock).Label()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/querier_mock_test.go:69 +0x164
  github.com/grafana/loki/pkg/querier.(*IngesterQuerier).Label.func1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/ingester_querier.go:145 +0x60
  github.com/grafana/loki/pkg/querier.(*IngesterQuerier).forGivenIngesters.func1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/ingester_querier.go:91 +0x108
  github.com/grafana/dskit/ring.DoUntilQuorum[go.shape.struct { github.com/grafana/loki/pkg/querier.addr string; github.com/grafana/loki/pkg/querier.response interface {} }].func1()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/grafana/dskit/ring/replication_set.go:218 +0x4c
  github.com/grafana/dskit/ring.DoUntilQuorumWithoutSuccessfulContextCancellation[go.shape.struct { github.com/grafana/loki/pkg/querier.addr string; github.com/grafana/loki/pkg/querier.response interface {} }].func2()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/grafana/dskit/ring/replication_set.go:297 +0xdc
  github.com/grafana/dskit/ring.DoUntilQuorumWithoutSuccessfulContextCancellation[go.shape.struct { github.com/grafana/loki/pkg/querier.addr string; github.com/grafana/loki/pkg/querier.response interface {} }].func5()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/grafana/dskit/ring/replication_set.go:303 +0x44

Previous write at 0x00c00073a248 by goroutine 119:
  github.com/grafana/loki/pkg/querier.TestIngesterQuerier_earlyExitOnQuorum.func5.1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/ingester_querier_test.go:91 +0x138
  github.com/stretchr/testify/mock.(*Mock).MethodCalled()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/stretchr/testify/mock/mock.go:552 +0xd3c
  github.com/stretchr/testify/mock.(*Mock).Called()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/stretchr/testify/mock/mock.go:464 +0x140
  github.com/grafana/loki/pkg/querier.(*querierClientMock).Label()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/querier_mock_test.go:69 +0x164
  github.com/grafana/loki/pkg/querier.(*IngesterQuerier).Label.func1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/ingester_querier.go:145 +0x60
  github.com/grafana/loki/pkg/querier.(*IngesterQuerier).forGivenIngesters.func1()
      /Users/progers/dev/src/github.com/grafana/loki/pkg/querier/ingester_querier.go:91 +0x108
  github.com/grafana/dskit/ring.DoUntilQuorum[go.shape.struct { github.com/grafana/loki/pkg/querier.addr string; github.com/grafana/loki/pkg/querier.response interface {} }].func1()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/grafana/dskit/ring/replication_set.go:218 +0x4c
  github.com/grafana/dskit/ring.DoUntilQuorumWithoutSuccessfulContextCancellation[go.shape.struct { github.com/grafana/loki/pkg/querier.addr string; github.com/grafana/loki/pkg/querier.response interface {} }].func2()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/grafana/dskit/ring/replication_set.go:297 +0xdc
  github.com/grafana/dskit/ring.DoUntilQuorumWithoutSuccessfulContextCancellation[go.shape.struct { github.com/grafana/loki/pkg/querier.addr string; github.com/grafana/loki/pkg/querier.response interface {} }].func5()
      /Users/progers/dev/src/github.com/grafana/loki/vendor/github.com/grafana/dskit/ring/replication_set.go:303 +0x44

after fix:

go test -count=50 -race . -run earlyExitOnQuorum
ok  	github.com/grafana/loki/pkg/querier	1.905s

Which issue(s) this PR fixes:
Relates to: #8586

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• CHANGELOG.md updated
  • If the change is worth mentioning in the release notes, add add-to-release-notes label
• Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
• For Helm chart changes bump the Helm chart version in production/helm/loki/Chart.yaml and update production/helm/loki/CHANGELOG.md and production/helm/loki/README.md. Example PR
• If the change is deprecating or removing a configuration option, update the deprecated-config.yaml and deleted-config.yaml files respectively in the tools/deprecated-config-checker directory. Example PR