fix(httplib): avoid tracing requests made by trace writers

[gnufede]

Description

Avoids tracing http requests made by trace writers to datadog internal services (i.e. prevents the ci visibility writer from sending traced requests to internal services).

Motivation

• Prevents tracing internals from being traced.
• Resolves flakiness in the httplib test suite with the agentless ci visibility writer

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

[mabdinur]

This is no longer a ci fix. It's more of a bug fix or chore. We should update the PR title and add a release note (if required).

[pr-commenter]

Benchmarks

Benchmark execution time: 2023-08-11 21:03:45

Comparing candidate commit 25725d7 in PR branch gnufede/fix-httplib-flakyness with baseline commit f843f74 in branch 1.x.

Found 1 performance improvements and 3 performance regressions! Performance is the same for 90 metrics, 0 unstable metrics.

scenario:sethttpmeta-obfuscation-disabled

• 🟩 max_rss_usage [-795.710KB; -649.359KB] or [-2.768%; -2.259%]

scenario:sethttpmeta-obfuscation-send-querystring-disabled

• 🟥 max_rss_usage [+634.510KB; +812.197KB] or [+2.249%; +2.879%]

scenario:sethttpmeta-obfuscation-worst-case-implicit-query

• 🟥 max_rss_usage [+619.745KB; +792.965KB] or [+2.196%; +2.810%]

scenario:span-start-finish

• 🟥 max_rss_usage [+603.437KB; +752.749KB] or [+2.166%; +2.702%]

[majorgreys]

This might be a good use case for the pin object on a connection instance. wdyt?

[gnufede]

This might be a good use case for the pin object on a connection instance. wdyt?

I tried that but didn't work for me, when disabled, it would disable the tracer for the whole integration, maybe further work is required for it to work as expected?