$ git clone -n https://src.fedoraproject.org/rpms/perl-Math-Base36.git /var/lib/mock/f45-build-24669-605/root/chroot_tmpdir/scmroot/perl-Math-Base36
Cloning into '/var/lib/mock/f45-build-24669-605/root/chroot_tmpdir/scmroot/perl-Math-Base36'...
$ git fetch origin 839b055bca92fde9856a07e06a4a5ff48734ba90:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Math-Base36
 * [new ref]         839b055bca92fde9856a07e06a4a5ff48734ba90 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 839b055 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild