fix(glrepo): handle api_host subdirectory when git SSH host differs
Description
When api_host contains a subdirectory (e.g., "gitlab.example.com/gitlab") but the git remote uses a different SSH host (e.g., "git.example.com"), the git URL path won't contain the subdirectory. The previous code incorrectly attempted to strip a non-existent subdirectory.
This fix uses strings.TrimPrefix which safely handles both cases:
- Path contains subdirectory: strips it
- Path doesn't contain subdirectory: returns path unchanged
Related Issues
Resolves #8146
How has this been tested?
Adds test case for separate git SSH host with api_host subdirectory.
Also tested via daily use with our hosted gitlab setup that follows this pattern.