fix(setup): out-of-memory error [backport 1.18]

[github-actions]

Backport 07f59ac from #6792 to 1.18.

When running setup.py extensions with the CMake parameter "-j", it could potentially raise an out-of-memory error. If someone wants to expedite the ddtrace installation, they should manually set the "CMAKE_BUILD_PARALLEL_LEVEL" environment variable.

Checklist

• Change(s) are motivated and described in the PR description.
• Testing strategy is described if automated tests are not included in the PR.
• Risk is outlined (performance impact, potential for breakage, maintainability, etc).
• Change is maintainable (easy to change, telemetry, documentation).
• Library release note guidelines are followed. If no release note is required, add label changelog/no-changelog.
• Documentation is included (in-code, generated user docs, public corp docs).
• Backport labels are set (if applicable)

Reviewer Checklist

• Title is accurate.
• No unnecessary changes are introduced.
• Description motivates each change.
• Avoids breaking API changes unless absolutely necessary.
• Testing strategy adequately addresses listed risk(s).
• Change is maintainable (easy to change, telemetry, documentation).
• Release note makes sense to a user of the library.
• Reviewer has explicitly 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]

Benchmarks

Benchmark execution time: 2023-08-31 10:11:06

Comparing candidate commit 7da70de in PR branch backport-6792-to-1.18 with baseline commit 9c036b7 in branch 1.18.

Found 1 performance improvements and 0 performance regressions! Performance is the same for 93 metrics, 0 unstable metrics.

scenario:samplingrules-high_match

• 🟩 max_rss_usage [-703.876KB; -609.711KB] or [-2.483%; -2.151%]