$ git clone -n https://src.fedoraproject.org/rpms/python-merge3.git /var/lib/mock/f45-build-31518-652/root/chroot_tmpdir/scmroot/python-merge3
Cloning into '/var/lib/mock/f45-build-31518-652/root/chroot_tmpdir/scmroot/python-merge3'...
$ git fetch origin d0fda2a8b9bc7f447affe8b6cfd73af8ef25b10a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-merge3
 * [new ref]         d0fda2a8b9bc7f447affe8b6cfd73af8ef25b10a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d0fda2a Use the provisional pyproject declarative buildsystem