chore(ci_visibility): add setting tags to manual testing API

[romainkomorndatadog]

Adds the ability to set tags via the manual testing API.
Fixes a couple of issues around child status fetching and finishing items.
Adds some more interesting tests.
Moves a bunch of log messages to debug level.

No changelog since it's unreleased.

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

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: romain.komorn/CIVIS-2943/add_setting_tags_and_fix_small_bugs
Commit report: a7c200c
Test service: dd-trace-py

✅ 0 Failed, 68 Passed, 36232 Skipped, 6m 36.81s Total duration (52m 49.21s time saved)

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-03-26 09:56:42

Comparing candidate commit 630615a in PR branch romain.komorn/CIVIS-2943/add_setting_tags_and_fix_small_bugs with baseline commit 9707da1 in branch main.

Found 2 performance improvements and 1 performance regressions! Performance is the same for 198 metrics, 9 unstable metrics.

scenario:flasksimple-appsec-get

• 🟥 execution_time [+218.214µs; +270.906µs] or [+3.493%; +4.337%]

scenario:flasksimple-tracer

• 🟩 execution_time [-265.807µs; -212.868µs] or [-4.091%; -3.276%]

scenario:httppropagationextract-none_propagation_style

• 🟩 max_rss_usage [-759.546KB; -616.301KB] or [-3.474%; -2.819%]