Fix Go extractor incorrectly excluding packages with .. in relative paths

[allsmog]

Summary

Fixes a bug where cross-module workspace dependencies were incorrectly excluded from extraction.

Problem

When using go.work workspaces with multiple modules:

1. Only input packages ModDirs were added to wantedRoots
2. Cross-module dependencies had their ModDir excluded
3. Checking dependencies against sibling packages produced .. paths → excluded

Example

/project/
  go.work
  configmodule/config/config.go  <-- Excluded
  mainmodule/app/jobs/worker/worker.go

Solution

Add ModDir to wantedRoots for all packages (6-line change in type extraction loop).

Testing

Integration test at go/ql/integration-tests/package-exclusion-fix/:

• Without fix: 2 files (config.go missing)
• With fix: 4 files (config.go present)

Run: pytest go/ql/integration-tests/package-exclusion-fix/

Impact

Low risk, high value for multi-module workspaces, backward compatible.

[owen-mc]

Thank you for this contribution to CodeQL. Would it be possible to turn your example into a test, to make it easier to confirm that this was failing without your change and passing with it, and to make sure it doesn't regress in future? You could start with a copy of go/ql/integration-tests/two-go-mods-not-nested/ (or one of its siblings) to get the basic structure. To run this test, the command pytest go/ql/integration-tests/two-go-mods-not-nested/ from the repository root should work.