$ git clone -n https://src.fedoraproject.org/rpms/atasm.git /var/lib/mock/f42-build-side-1-3505981-45995/root/chroot_tmpdir/scmroot/atasm
Cloning into '/var/lib/mock/f42-build-side-1-3505981-45995/root/chroot_tmpdir/scmroot/atasm'...
$ git fetch origin 96f7bf4a380e7bb326937cb816f36e613f1cf9a9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/atasm
 * [new ref]         96f7bf4a380e7bb326937cb816f36e613f1cf9a9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 96f7bf4 - update to 1.26 (rhbz#2344023)