Loki ignores JAEGER_SERVICE_NAME env variable

[rlex]

Describe the bug
Loki ignores JAEGER_SERVICE_NAME env variable

To Reproduce
Enable tracing of any loki container like this, redefining service name

          extraEnv:
            - name: JAEGER_SERVICE_NAME
              value: 'loki-stg-ingester'
            - name: JAEGER_AGENT_HOST
              valueFrom:
                fieldRef:
                  fieldPath: status.hostIP
            - name: JAEGER_AGENT_PORT
              value: '6831'
            - name: JAEGER_SAMPLER_TYPE
              value: const
            - name: JAEGER_SAMPLER_PARAM
              value: '1.0'

Expected behavior
Traces should appear as loki-stg-ingester service name, but appear as loki-ingester. Hardcoded somewhere?

[stale]

Hi! This issue has been automatically marked as stale because it has not had any
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