Merge branch 'feature/e2e-github-username' into 'master'

Make E2E `github_username` more flexible

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/105173



Merged-by: Sanad Liaquat <sliaquat@gitlab.com>
Approved-by: Sanad Liaquat <sliaquat@gitlab.com>
Approved-by: Kevin Morrison <kmorrison@gitlab.com>
Co-authored-by: Song Huang <songhuang@gitlab.cn>