$ git clone -n https://src.fedoraproject.org/rpms/ruby-gnome2.git /var/lib/mock/f39-build-1596300-38363/root/chroot_tmpdir/scmroot/ruby-gnome2
Cloning into '/var/lib/mock/f39-build-1596300-38363/root/chroot_tmpdir/scmroot/ruby-gnome2'...
$ git fetch origin abea59dc0609a44ff8ef8a4bd78a0880c675a428:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ruby-gnome2
 * [new ref]         abea59dc0609a44ff8ef8a4bd78a0880c675a428 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at abea59d add missing BR