feat(asm): standalone asm initiative

[christophe-papazian]

Add a new env var to be able to start the tracer in ASM mode only.

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[bot]]

Benchmarks

Benchmark execution time: 2023-09-22 08:40:03

Comparing candidate commit 2981f93f676bf648fe66d93a75e150c18bca9fe6 in PR branch christophe-papazian/APPSEC-10770-asm-tracer-beta-of-standalone-asm with baseline commit e67dcb744d7115370c2751a1082cb988b415bfde in branch 2.x.

Found 0 performance improvements and 1 performance regressions! Performance is the same for 89 metrics, 0 unstable metrics.

scenario:sethttpmeta-useragentvariant_not_exists_1

• 🟥 execution_time [+1.975µs; +2.320µs] or [+2.065%; +2.426%]