[PROMETHEUS_EXPORTER] Fix default for emitting otel_scope attributes

[yashykt]

Fixes #3170

Changes

Fixes the default behavior of emitting otel_scope attributes.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.86%. Comparing base (955a807) to head (64a58ca).
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        6151     6151           
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  Hits         5404     5404           
  Misses        747      747           

[marcalff]

From the spec:

A Prometheus Exporter MAY support a configuration option to produce metrics without a scope info metric, or scope labels. The option MAY be named without_scope_info, and MUST be false by default.

so this PR is indeed the expected behavior.

[marcalff]

LGTM, thanks for the fix.