$ git clone -n https://src.fedoraproject.org/rpms/perl-JSON-Parse.git /var/lib/mock/f41-build-815974-149916/root/chroot_tmpdir/scmroot/perl-JSON-Parse
Cloning into '/var/lib/mock/f41-build-815974-149916/root/chroot_tmpdir/scmroot/perl-JSON-Parse'...
$ git fetch origin 8d66fd3ffac470291d9a16c4ba2f75cdc4491f27:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-JSON-Parse
 * [new ref]         8d66fd3ffac470291d9a16c4ba2f75cdc4491f27 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8d66fd3 Perl 5.40 rebuild