ci(system-tests): don't skip on main branch

[gnufede]

Checklist

• [ ] Change(s) are motivated and described in the PR description
• [ ] Testing strategy is described if automated tests are not included in the PR
• [ ] Risks are described (performance impact, potential for breakage, maintainability)
• [ ] Change is maintainable (easy to change, telemetry, documentation)
• [ ] Library release note guidelines are followed or label changelog/no-changelog is set
• [ ] Documentation is included (in-code, generated user docs, public corp docs)
• [ ] Backport labels are set (if applicable)
• [ ] If this PR changes the public interface, I've notified @DataDog/apm-tees.
• [ ] If change touches code that signs or publishes builds or packages, or handles credentials of any kind, I've requested a review from @DataDog/security-design-and-guidance.

Reviewer Checklist

• [ ] Title is accurate
• [ ] All changes are related to the pull request's stated goal
• [ ] Description motivates each change
• [ ] Avoids breaking API changes
• [ ] Testing strategy adequately addresses listed risks
• [ ] Change is maintainable (easy to change, telemetry, documentation)
• [ ] Release note makes sense to a user of the library
• [ ] 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

[pr-commenter[bot]]

Benchmarks

Benchmark execution time: 2024-02-07 18:29:41

Comparing candidate commit e2126e96c878db5ae741e489fa1a1e054e8ba482 in PR branch gnufede/ci-system-tests-main with baseline commit 9b0f9c828c60ccb52dab58ed5181282422c5ff92 in branch main.

Found 7 performance improvements and 1 performance regressions! Performance is the same for 187 metrics, 9 unstable metrics.

scenario:httppropagationextract-all_styles_all_headers

• 🟩 max_rss_usage [-758.534KB; -654.586KB] or [-2.527%; -2.181%]

scenario:httppropagationextract-b3_single_headers

• 🟩 max_rss_usage [-783.586KB; -677.457KB] or [-2.611%; -2.258%]

scenario:httppropagationextract-empty_headers

• 🟩 max_rss_usage [-993.100KB; -887.374KB] or [-3.312%; -2.959%]

scenario:httppropagationextract-large_header_no_matches

• 🟩 max_rss_usage [-769.197KB; -640.237KB] or [-2.563%; -2.133%]

scenario:httppropagationextract-medium_header_no_matches

• 🟩 max_rss_usage [-794.195KB; -693.472KB] or [-2.645%; -2.309%]

scenario:httppropagationextract-none_propagation_style

• 🟥 max_rss_usage [+620.000KB; +730.041KB] or [+2.110%; +2.484%]

scenario:httppropagationextract-wsgi_empty_headers

• 🟩 max_rss_usage [-753.072KB; -644.074KB] or [-2.509%; -2.146%]

scenario:httppropagationextract-wsgi_invalid_trace_id_header

• 🟩 max_rss_usage [-828.197KB; -723.777KB] or [-2.755%; -2.407%]