Propagate TraceContext from producer to consumer

[gam-phon]

@vmihailenco Thank you for taskq and the support of opentelemetry out of the box in your libraries.

In taskqext/otel.go, support tracing with opentelemetry while processing the message in the worker not in the producer as well. I have a trace started in the producer I want to propagate this to the consumer as async trace. I want to pass trace information to consumers.