$ git clone -n https://src.fedoraproject.org/rpms/perl-XML-SAX-Writer.git /var/lib/mock/f45-build-27542-624/root/chroot_tmpdir/scmroot/perl-XML-SAX-Writer
Cloning into '/var/lib/mock/f45-build-27542-624/root/chroot_tmpdir/scmroot/perl-XML-SAX-Writer'...
$ git fetch origin 293b567f632d0a29d9415e87ddaeb7219b22f8f0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-XML-SAX-Writer
 * [new ref]         293b567f632d0a29d9415e87ddaeb7219b22f8f0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 293b567 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild