$ git clone -n https://src.fedoraproject.org/rpms/calls.git /var/lib/mock/f40-build-801513-143805/root/chroot_tmpdir/scmroot/calls
Cloning into '/var/lib/mock/f40-build-801513-143805/root/chroot_tmpdir/scmroot/calls'...
$ git fetch origin 4245e7462bef0f897350b07ad24db2a28bb74c6f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/calls
 * [new ref]         4245e7462bef0f897350b07ad24db2a28bb74c6f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4245e74 Upstream release 46.0