$ git clone -n https://src.fedoraproject.org/rpms/rust-url.git /var/lib/mock/f45-build-46021-830/root/chroot_tmpdir/scmroot/rust-url
Cloning into '/var/lib/mock/f45-build-46021-830/root/chroot_tmpdir/scmroot/rust-url'...
$ git fetch origin 52dcedb33e3e3ec449e5d0b62cab89e3c36e1fab:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-url
 * [new ref]         52dcedb33e3e3ec449e5d0b62cab89e3c36e1fab -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 52dcedb Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild