$ git clone -n https://src.fedoraproject.org/rpms/TOPCOM.git /var/lib/mock/f40-build-791142-137124/root/chroot_tmpdir/scmroot/TOPCOM
Cloning into '/var/lib/mock/f40-build-791142-137124/root/chroot_tmpdir/scmroot/TOPCOM'...
$ git fetch origin 201946d68331196fb7b51ef62c23621eddae1fc3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/TOPCOM
 * [new ref]         201946d68331196fb7b51ef62c23621eddae1fc3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 201946d Version 1.1.2