fix db test data race for queue tick interval

[fairclothjm]

Description

Attempt to fix a data race for the queue tick interval on the logical.BackendConfig map. I was unable to repro the data race locally, but I think reinitializing the BackendConfig for each value under test should fix the issue.

Failure: https://github.com/hashicorp/vault-enterprise/actions/runs/12584472353/job/35075729417

Test data race output:

WARNING: DATA RACE
Write at 0x00c00cedad80 by goroutine 29135:
  runtime.mapassign_faststr()
      /home/runner/actions-runner/_work/_tool/go/1.23.3/x64/src/runtime/map_faststr.go:223 +0x0
  github.com/hashicorp/vault/builtin/logical/database.TestQueueTickIntervalKeyConfig()
      /home/runner/actions-runner/_work/vault-enterprise/vault-enterprise/builtin/logical/database/rotation_test.go:1045 +0x308
  testing.tRunner()
      /home/runner/actions-runner/_work/_tool/go/1.23.3/x64/src/testing/testing.go:1690 +0x226
  testing.(*T).Run.gowrap1()
      /home/runner/actions-runner/_work/_tool/go/1.23.3/x64/src/testing/testing.go:1743 +0x44

Previous read at 0x00c00cedad80 by goroutine 37721:
  runtime.mapaccess2_faststr()
      /home/runner/actions-runner/_work/_tool/go/1.23.3/x64/src/runtime/map_faststr.go:117 +0x0
  github.com/hashicorp/vault/builtin/logical/database.(*databaseBackend).initQueue()
      /home/runner/actions-runner/_work/vault-enterprise/vault-enterprise/builtin/logical/database/rotation.go:622 +0x6c8
  github.com/hashicorp/vault/builtin/logical/database.Factory.gowrap1()
      /home/runner/actions-runner/_work/vault-enterprise/vault-enterprise/builtin/logical/database/backend.go:76 +0x5d

TODO only if you're a HashiCorp employee

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  applying the patch for this PR to the ENT repo and running tests doesn't
  break any tests. Sometimes ENT only tests rely on public functions in CE
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[github-actions]

CI Results:
All Go tests succeeded! ✅

[github-actions]

Build Results:
All builds succeeded! ✅

[helenfufu]

Reinitializing the config in separate subtests makes sense to me!

[stevendpclark]

Thanks for addressing this!