Add index to package files on package_id, status and file extension

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/153993



Merged-by: Adam Hegyi <ahegyi@gitlab.com>
Approved-by: Moaz Khalifa <mkhalifa@gitlab.com>
Approved-by: Hunter Stewart <hustewart@gitlab.com>
Approved-by: Adam Hegyi <ahegyi@gitlab.com>
Reviewed-by: Moaz Khalifa <mkhalifa@gitlab.com>
Co-authored-by: Dzmitry Meshcharakou <12459192-dmeshcharakou@users.noreply.gitlab.com>