internal/civisibility: specify if the user is setting the DD_SERVICE

[tonyredondo]

What does this PR do?

This PR sets a tag to let the ci visibility backend know if the DD_SERVICE value was provided by the user or auto-generated.

Motivation

This required by the backend.

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.

Unsure? Have a question? Request a review!

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-11-25 16:46:44

Comparing candidate commit 65e70d8 in PR branch tony/user-provided-test-service-tag with baseline commit 58e1e63 in branch main.

Found 0 performance improvements and 1 performance regressions! Performance is the same for 57 metrics, 1 unstable metrics.

scenario:BenchmarkSetTagMetric-24

• 🟥 execution_time [+2.713ns; +4.527ns] or [+2.321%; +3.873%]