Remove redundant th / td classes in jobs app

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/98746



Merged-by: Olena Horal-Koretska <ohoralkoretska@gitlab.com>
Approved-by: Stanislav Lashmanov <slashmanov@gitlab.com>
Approved-by: Olena Horal-Koretska <ohoralkoretska@gitlab.com>
Co-authored-by: Justin Ho <hduong@gitlab.com>