$ git clone -n https://src.fedoraproject.org/rpms/ghc-panic.git /var/lib/mock/f45-build-10586-419/root/chroot_tmpdir/scmroot/ghc-panic
Cloning into '/var/lib/mock/f45-build-10586-419/root/chroot_tmpdir/scmroot/ghc-panic'...
$ git fetch origin 9a521dda736b7a600bb6ff80be62152d92b57295:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-panic
 * [new ref]         9a521dda736b7a600bb6ff80be62152d92b57295 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9a521dd Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild