$ git clone -n https://src.fedoraproject.org/rpms/glibmm2.4.git /var/lib/mock/f39-build-1469985-33873/root/chroot_tmpdir/scmroot/glibmm2.4
Cloning into '/var/lib/mock/f39-build-1469985-33873/root/chroot_tmpdir/scmroot/glibmm2.4'...
$ git fetch origin 9d74fce4dfffeb044a1d98bc26c17a4b8e78d980:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/glibmm2.4
 * [new ref]         9d74fce4dfffeb044a1d98bc26c17a4b8e78d980 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9d74fce Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild