exporters/zipkin: Add use new scope attributes

[Kielek]

Add otel.scope.name and otel.scope.version attributes to propagate scope according to https://github.com/open-telemetry/opentelemetry-specification/blob/v1.31.0/specification/common/mapping-to-non-otlp.md#instrumentationscope

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.8%. Comparing base (edb788b) to head (c3085fc).

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #5108   +/-   ##
=====================================
  Coverage   83.8%   83.8%           
=====================================
  Files        248     248           
  Lines      16201   16203    +2     
=====================================
+ Hits       13579   13581    +2     
  Misses      2334    2334           
  Partials     288     288           

Files	Coverage Δ
exporters/zipkin/model.go	93.9% <100.0%> (+<0.1%)	⬆️

The spec is not clear.

[pellared]

It took me some time to access if this change is specification compliant.

https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/common/mapping-to-non-otlp.md#instrumentationscope says:

OpenTelemetry InstrumentationScope's fields MUST be reported as key-value pairs associated with the Span, Metric Data Point or LogRecord using the following mapping:

But then all the attributes are marked as Recommended. I guess it mean that it is left to the exporter to decide how the instrumentation scope is propagated.

Also from https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/sdk_exporters/zipkin.md:

The generic transformation rules specified here also apply. If a particular generic transformation rule and the rule in this document contradict then the rule in this document MUST be used.

Personally, I am approving as I think the change is aligned with the specification.