ci: Use bare-metal OTEL runners for benchmark CI

[scottgerring]

Fixes #
Design discussion issue (if applicable) #

Changes

Please provide a brief description of the changes here.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.3%. Comparing base (1bce83f) to head (18e8718).
Report is 11 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #2813   +/-   ##
=====================================
  Coverage   80.3%   80.3%           
=====================================
  Files        124     124           
  Lines      23333   23333           
=====================================
+ Hits       18754   18758    +4     
+ Misses      4579    4575    -4     

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[scottgerring]

Following on from open-telemetry/community/issues/2616 , this PR moves our criterion suite to use the self-hosted OTEL runners. Waiting to see it run through once successfully before marking ready-for-review.

Also noted in the golang benchmarks, that the jobs themselves can output markdown. This would solve our "can't annotate the PR with results" thing nicely. Will try work out what we're missing for this to work.