contrib/net/http: Make DD_TRACE_HTTP_CLIENT_TAG_QUERY_STRING false by default

[mtoffl01]

What does this PR do?

By default, query string is not collected on http client spans.

Motivation

Without the ability to obfuscate the query string (like what DD_TRACE_OBFUSCATION_QUERY_STRING_REGEXP does for http server spans), collecting it by default poses a security risk. Thus, we are disabling it by default, allowing users to opt-in to the feature if they so choose.

Reviewer's Checklist

• Changed code has unit tests for its functionality at or near 100% coverage.
• System-Tests covering this feature have been added and enabled with the va.b.c-dev version tag.
• There is a benchmark for any new code, or changes to existing code.
• If this interacts with the agent in a new way, a system test has been added.
• Add an appropriate team label so this PR gets put in the right place for the release notes.
• Non-trivial go.mod changes, e.g. adding new modules, are reviewed by @DataDog/dd-trace-go-guild.
• For internal contributors, a matching PR should be created to the v2-dev branch and reviewed by @DataDog/apm-go.

Unsure? Have a question? Request a review!

[datadog-datadog-prod-us1]

Datadog Report

Branch report: mtoff/disalbe-client-querystring
Commit report: 88876ae
Test service: dd-trace-go

✅ 0 Failed, 5094 Passed, 67 Skipped, 2m 57.35s Total Time

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-12-09 11:01:48

Comparing candidate commit a5b4b0e in PR branch mtoff/disalbe-client-querystring with baseline commit 79a1f60 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 59 metrics, 0 unstable metrics.