$ git clone -n https://src.fedoraproject.org/rpms/rust-size.git /var/lib/mock/f45-build-44991-820/root/chroot_tmpdir/scmroot/rust-size
Cloning into '/var/lib/mock/f45-build-44991-820/root/chroot_tmpdir/scmroot/rust-size'...
$ git fetch origin f5942ea075a361cbe38c29c3d69341ef9cedd01e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-size
 * [new ref]         f5942ea075a361cbe38c29c3d69341ef9cedd01e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f5942ea Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild