$ git clone -n https://src.fedoraproject.org/rpms/perl-Perlbal-XS-HTTPHeaders.git /var/lib/mock/f41-build-1108038-20090/root/chroot_tmpdir/scmroot/perl-Perlbal-XS-HTTPHeaders
Cloning into '/var/lib/mock/f41-build-1108038-20090/root/chroot_tmpdir/scmroot/perl-Perlbal-XS-HTTPHeaders'...
$ git fetch origin 6134f1282e49710869ae678d379a244334603565:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Perlbal-XS-HTTPHeaders
 * [new ref]         6134f1282e49710869ae678d379a244334603565 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6134f12 Perl 5.40 rebuild