$ git clone -n https://src.fedoraproject.org/rpms/xkill.git /var/lib/mock/f40-build-2234248-53396/root/chroot_tmpdir/scmroot/xkill
Cloning into '/var/lib/mock/f40-build-2234248-53396/root/chroot_tmpdir/scmroot/xkill'...
$ git fetch origin 48780ba676d7808c8a4ac1f027989c610797ae20:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xkill
 * [new ref]         48780ba676d7808c8a4ac1f027989c610797ae20 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 48780ba SPDX migration