$ git clone -n https://src.fedoraproject.org/rpms/perl-Ace.git /var/lib/mock/f45-build-21552-586/root/chroot_tmpdir/scmroot/perl-Ace
Cloning into '/var/lib/mock/f45-build-21552-586/root/chroot_tmpdir/scmroot/perl-Ace'...
$ git fetch origin 2e1d176dc08f7fbf390df41e66d9869e4bbac746:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Ace
 * [new ref]         2e1d176dc08f7fbf390df41e66d9869e4bbac746 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2e1d176 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild