Fix Zipkin spanFormat (#5261)

<!--
!! Please DELETE this comment before posting.
We appreciate your contribution to the Jaeger project! 👋🎉
-->

## Which problem is this PR solving?
- <!-- Example: Resolves #123 -->
Resolves #5260
## Description of the changes
- 

## How was this change tested?
- 

## Checklist
- [ ] I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [ ] I have signed all commits
- [ ] I have added unit tests for the new functionality
- [ ] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `yarn lint` and `yarn test`

Signed-off-by: Yuan Fang <yuanfang@alauda.io>
Co-authored-by: Yuri Shkuro <yurishkuro@users.noreply.github.com>

cmd/collector/app/handler/zipkin_receiver.go

@@ -69,6 +69,9 @@ func startZipkinReceiver(
 	}
 
 	consumerAdapter := newConsumerDelegate(logger, spanProcessor, tm)
+	// reset Zipkin spanFormat
+	consumerAdapter.batchConsumer.spanOptions.SpanFormat = processor.ZipkinSpanFormat
+
 	nextConsumer, err := newTraces(consumerAdapter.consume)
 	if err != nil {
 		return nil, fmt.Errorf("could not create Zipkin consumer: %w", err)

cmd/collector/app/handler/zipkin_receiver_test.go

@@ -23,6 +23,7 @@ import (
 	"go.opentelemetry.io/collector/receiver"
 
 	"github.com/jaegertracing/jaeger/cmd/collector/app/flags"
+	"github.com/jaegertracing/jaeger/cmd/collector/app/processor"
 	zipkinthrift "github.com/jaegertracing/jaeger/model/converter/thrift/zipkin"
 	"github.com/jaegertracing/jaeger/pkg/tenancy"
 	"github.com/jaegertracing/jaeger/pkg/testutils"
@@ -126,6 +127,7 @@ func TestZipkinReceiver(t *testing.T) {
 				t.Logf("response: %s %s", response.Status, string(bodyBytes))
 			}
 			require.NoError(t, response.Body.Close())
+			require.Equal(t, processor.ZipkinSpanFormat, spanProcessor.getSpanFormat())
 		})
 	}
 }