$ git clone -n https://src.fedoraproject.org/rpms/swayimg.git /var/lib/mock/f42-build-side-1-3586946-46926/root/chroot_tmpdir/scmroot/swayimg
Cloning into '/var/lib/mock/f42-build-side-1-3586946-46926/root/chroot_tmpdir/scmroot/swayimg'...
$ git fetch origin 271e2c4f3fc9369e5bde09f22df9511f1560d77b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/swayimg
 * [new ref]         271e2c4f3fc9369e5bde09f22df9511f1560d77b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 271e2c4 Update to 4.5