[9.14] Update GitLab CI to Fedora 31
Since Fedora 31 is the current Fedora release, replace Fedora 30 GitLab CI jobs with their up-to-date counterparts.
(cherry picked from commit b36f5496)
Since Fedora 31 is the current Fedora release, replace Fedora 30 GitLab CI jobs with their up-to-date counterparts.
(cherry picked from commit b36f5496)