Merge branch '26169-refactor-uses_default_ci_config' into 'master'

Delete Project#uses_default_ci_config?

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/142892



Merged-by: drew stachon <730684-drew@users.noreply.gitlab.com>
Approved-by: Leaminn Ma <lma@gitlab.com>
Approved-by: drew stachon <730684-drew@users.noreply.gitlab.com>
Co-authored-by: Furkan Ayhan <furkanayhn@gmail.com>