$ git clone -n https://src.fedoraproject.org/rpms/catch.git /var/lib/mock/f40-build-1931508-25121/root/chroot_tmpdir/scmroot/catch
Cloning into '/var/lib/mock/f40-build-1931508-25121/root/chroot_tmpdir/scmroot/catch'...
$ git fetch origin 64fbda0ad1c9286adc80c533577c90d3ba6e2217:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/catch
 * [new ref]         64fbda0ad1c9286adc80c533577c90d3ba6e2217 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 64fbda0 Update to 3.5.3 upstream release