$ git clone -n https://src.fedoraproject.org/rpms/perl-String-Interpolate-Named.git /var/lib/mock/f42-build-side-1-3589238-46955/root/chroot_tmpdir/scmroot/perl-String-Interpolate-Named
Cloning into '/var/lib/mock/f42-build-side-1-3589238-46955/root/chroot_tmpdir/scmroot/perl-String-Interpolate-Named'...
$ git fetch origin eb8527cc2a80fc8b272511bd6eac06630fb57717:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-String-Interpolate-Named
 * [new ref]         eb8527cc2a80fc8b272511bd6eac06630fb57717 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eb8527c Upgrade to upstream.