$ git clone -n https://src.fedoraproject.org/rpms/perl-libxml-perl.git /var/lib/mock/f45-build-27694-625/root/chroot_tmpdir/scmroot/perl-libxml-perl
Cloning into '/var/lib/mock/f45-build-27694-625/root/chroot_tmpdir/scmroot/perl-libxml-perl'...
$ git fetch origin c464990e10810535f853dcdbeb46b9ea9b08488e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-libxml-perl
 * [new ref]         c464990e10810535f853dcdbeb46b9ea9b08488e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c464990 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild