$ git clone -n https://src.fedoraproject.org/rpms/gnome-nibbles.git /var/lib/mock/f39-build-2070811-49324/root/chroot_tmpdir/scmroot/gnome-nibbles
Cloning into '/var/lib/mock/f39-build-2070811-49324/root/chroot_tmpdir/scmroot/gnome-nibbles'...
$ git fetch origin 38e3b5f971997efbbf07ce98ef85d3574a730241:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-nibbles
 * [new ref]         38e3b5f971997efbbf07ce98ef85d3574a730241 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 38e3b5f Update to 4.0.1