[EXPORTER] add instrumentation scope attributes to otlp proto messages for traces and metrics

[dbarker]

Fixes #3184

Changes

Please provide a brief description of the changes here.

• Adds a new overload of the PopulateAttribute method to set attributes on the proto::common::v1::InstrumentationScope object in otlp_populate_attribute_utils.h
• Sets the instrumentation scope attributes of proto::common::v1::InstrumentationScope in the OtlpRecordableUtils::PopulateRequest method for traces.
• Sets the instrumentation scope attributes in proto::common::v1::InstrumentationScope in the OtlpMetricUtils::PopulateResourceMetrics method for metrics
• Updates the following test files to check that instrumentation scope attributes are set
  • otlp_file_exporter_test.cc
  • otlp_file_metric_exporter_test.cc
  • otlp_metrics_serialization_test.cc
  • otlp_recordable_test.cc
• Fixes a bug found with the new tests where the schemaUrl for the metrics instrumentation scope was being set to the schemaUrl for metrics resource.

For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: dbarker / name: Doug Barker (61e5dff, 3e15cce, f18869b, 2f0740f, 5e07f05, 69a1dc7, b59ac58, ffe966d, 015fb00, dc98669)
• ✅ login: marcalff / name: Marc Alff (a910e4e)

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.86%. Comparing base (2d80c18) to head (ffe966d).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   87.86%   87.86%           
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  Files         195      195           
  Lines        6153     6153           
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  Misses        747      747           

[dbarker]

I've updated this PR with more tests and its passing CI. Ready for review.

[marcalff]

LGTM, thanks for the fix.

One minor comment to address, with approval to follow.

[marcalff]

LGTM, thanks for the fix.

Nice work.

[owent]

LGTM, thanks.