$ git clone -n https://src.fedoraproject.org/rpms/gap-pkg-polymaking.git /var/lib/mock/f39-build-1599482-38517/root/chroot_tmpdir/scmroot/gap-pkg-polymaking
Cloning into '/var/lib/mock/f39-build-1599482-38517/root/chroot_tmpdir/scmroot/gap-pkg-polymaking'...
$ git fetch origin 21d8e4f9eaa37b0e2746aec5cae3a1fe66f2b1e1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gap-pkg-polymaking
 * [new ref]         21d8e4f9eaa37b0e2746aec5cae3a1fe66f2b1e1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21d8e4f Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild