$ git clone -n https://src.fedoraproject.org/rpms/dumb.git /var/lib/mock/f41-build-1018491-17947/root/chroot_tmpdir/scmroot/dumb
Cloning into '/var/lib/mock/f41-build-1018491-17947/root/chroot_tmpdir/scmroot/dumb'...
$ git fetch origin aeab15288237e0a0ba08373e158c8b9c808d054a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dumb
 * [new ref]         aeab15288237e0a0ba08373e158c8b9c808d054a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aeab152 Eliminate use of obsolete %patchN syntax (#2283636)