$ git clone -n https://src.fedoraproject.org/rpms/perl-Math-BigInt.git /var/lib/mock/f45-build-24670-605/root/chroot_tmpdir/scmroot/perl-Math-BigInt
Cloning into '/var/lib/mock/f45-build-24670-605/root/chroot_tmpdir/scmroot/perl-Math-BigInt'...
$ git fetch origin 0aacaa45421adb412860600d1428b81fb1be31f3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Math-BigInt
 * [new ref]         0aacaa45421adb412860600d1428b81fb1be31f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0aacaa4 Increase release to favour standalone package