Revert !3799 "Remove all the unnecessary LANGUAGE pragmas"
!3799 (closed) breaks master on windows (see https://gitlab.haskell.org/Kleidukos/ghc/-/jobs/409523) so reverting for now.
!3799 (closed) breaks master on windows (see https://gitlab.haskell.org/Kleidukos/ghc/-/jobs/409523) so reverting for now.