ci: add codeowners to gotestsum report

[hannahkm]

What does this PR do?

Adds a script to enable reporting CODEOWNER to CI. Adding the file parameter to our XML report file will allow the DataDog CI to compare against our CODEOWNERS file and assign tags to each test in the backend, as detailed in our docs.

The XML file already contains, for each testcase, a className attribute that represents the full path to the test. For example,

className=gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer

To derive the subdirectory, which would match lines in our existing CODEOWNERS file, we trim the beginning:

file=/ddtrace/tracer

Note: the DataDog CI and JUnit XML will only recognize the file attribute if it is the last attribute in the testcase line.

Motivation

When triaging failing or flaky tests, it's helpful to see at a glance who is responsible for a certain file or directory. This is already available in dd-trace-py, dd-trace-java, and dd-trace-rb.

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!

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-01-28 16:24:42

Comparing candidate commit 5095868 in PR branch hannahkm/add-codeowners with baseline commit f0ed584 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 58 metrics, 1 unstable metrics.

[datadog-datadog-prod-us1]

Datadog Report

Branch report: hannahkm/add-codeowners
Commit report: 6e34e02
Test service: dd-trace-go

✅ 0 Failed, 5216 Passed, 72 Skipped, 2m 19.67s Total Time