$ git clone -n https://src.fedoraproject.org/rpms/perl-CGI-FormBuilder.git /var/lib/mock/f45-build-21977-589/root/chroot_tmpdir/scmroot/perl-CGI-FormBuilder
Cloning into '/var/lib/mock/f45-build-21977-589/root/chroot_tmpdir/scmroot/perl-CGI-FormBuilder'...
$ git fetch origin 74046ae923987b600515f7b00ef1ebafe7b9a97a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-CGI-FormBuilder
 * [new ref]         74046ae923987b600515f7b00ef1ebafe7b9a97a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 74046ae Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild