chore(telemetry): benchmark to track impact of metrics

[wantsui]

Related to the efforts in #12430. I separated the benchmarks in a separate PR since it doesn't need to be tied up with that PR.

The goal of this PR is to add the benchmark measuring the impact of creating instrumentation telemetry metrics.

Credits: @erikayasuda and @brettlangdon for pairing with me on this and checking out the results!

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[github-actions]

CODEOWNERS have been resolved as:

benchmarks/telemetry_add_metric/config.yaml                             @DataDog/apm-core-python
benchmarks/telemetry_add_metric/scenario.py                             @DataDog/apm-core-python
.gitlab/benchmarks/microbenchmarks.yml                                  @DataDog/python-guild @DataDog/apm-core-python

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 3.69%. Comparing base (8c4d62d) to head (7ff2789).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #12559      +/-   ##
==========================================
- Coverage    3.69%    3.69%   -0.01%     
==========================================
  Files        1359     1359              
  Lines      133666   133666              
==========================================
- Hits         4940     4938       -2     
- Misses     128726   128728       +2     

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[brettlangdon]

if you want to also run this as part of the microbenchmarks CI job, you need to add it to the list in .gitlab/benchmarks/micrbenchmarks.yml

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: wantsui/add-benchmark-for-adding-metrics
Commit report: dc15d86
Test service: dd-trace-py

✅ 0 Failed, 43 Passed, 215 Skipped, 51.63s Total duration (5m 13.11s time saved)

[brettlangdon]

The check regressions job is failing because this new job doesn't exist on main, manually merging rather than removing, merging, and then adding in a new PR.