$ git clone -n https://src.fedoraproject.org/rpms/rust-stable-pattern.git /var/lib/mock/f45-build-45155-821/root/chroot_tmpdir/scmroot/rust-stable-pattern
Cloning into '/var/lib/mock/f45-build-45155-821/root/chroot_tmpdir/scmroot/rust-stable-pattern'...
$ git fetch origin 34be9fe1422a7c69c4a92bb759502d0dca2e8f4e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-stable-pattern
 * [new ref]         34be9fe1422a7c69c4a92bb759502d0dca2e8f4e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 34be9fe Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild