$ git clone -n https://src.fedoraproject.org/rpms/swayimg.git /var/lib/mock/f42-build-side-1-3584890-46899/root/chroot_tmpdir/scmroot/swayimg
Cloning into '/var/lib/mock/f42-build-side-1-3584890-46899/root/chroot_tmpdir/scmroot/swayimg'...
$ git fetch origin 6beb91e7d1478ee0aa6cd79644f2b057a8d564a0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/swayimg
 * [new ref]         6beb91e7d1478ee0aa6cd79644f2b057a8d564a0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6beb91e Update to 4.4 (#2376803)