$ git clone -n https://src.fedoraproject.org/rpms/perl-Perl6-Junction.git /var/lib/mock/f45-build-25824-613/root/chroot_tmpdir/scmroot/perl-Perl6-Junction
Cloning into '/var/lib/mock/f45-build-25824-613/root/chroot_tmpdir/scmroot/perl-Perl6-Junction'...
$ git fetch origin 54fbeac3b944ac294e3032a7c388c2f28d145d57:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Perl6-Junction
 * [new ref]         54fbeac3b944ac294e3032a7c388c2f28d145d57 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 54fbeac Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild