$ git clone -n https://src.fedoraproject.org/rpms/perl-Plack.git /var/lib/mock/f39-build-2255211-54237/root/chroot_tmpdir/scmroot/perl-Plack
Cloning into '/var/lib/mock/f39-build-2255211-54237/root/chroot_tmpdir/scmroot/perl-Plack'...
$ git fetch origin 0b60ca6e37de2e266e4ae7d2a5b35d0637e26353:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Plack
 * [new ref]         0b60ca6e37de2e266e4ae7d2a5b35d0637e26353 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0b60ca6 Update to 1.0051.