ci(opentelemetry): pin opentelemetry-api version to unblock tests [backport 2.9]

[github-actions]

Backport 27cd94c from #9932 to 2.9.

Resolves the following failures: https://app.circleci.com/pipelines/github/DataDog/dd-trace-py/66676/workflows/fa3470d[…]2a-d3447f3f431a/jobs/4095885/parallel-runs/2?filterBy=FAILED in ci.

The opentelemetry-api broke compatibility with ddtrace in v1.25.0 and then introduced another breaking change in 1.26.0. This PR ensures the telemetry test suite uses a stable version of the opentelemetry-api.

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

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: backport-9932-to-2.9
Commit report: 1e8850b
Test service: dd-trace-py

✅ 0 Failed, 174257 Passed, 1508 Skipped, 11h 39m 27.77s Total duration (2m 49.72s time saved)
❄️ 1 New Flaky
⌛ 1 Performance Regression

New Flaky Tests (1)

• test_span_schematization[None-v0] - test_graphql.py - Last Failure

  Expand for error

   sent 629B in 1.14308s to http://localhost:9126/v0.5/traces
     
   assert b'sent 629B i...v0.5/traces\n' == b''
     Use -v to get more diff
  

⌛ Performance Regressions vs Default Branch (1)

• test_schematized_operation_names[v0] - test_djangorestframework.py 6.99s (+5.6s, +403%) - Details

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-07-25 15:50:29

Comparing candidate commit 1e8850b in PR branch backport-9932-to-2.9 with baseline commit 7ee32df in branch 2.9.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 193 metrics, 9 unstable metrics.