$ git clone -n https://src.fedoraproject.org/rpms/rust-gstreamer-pbutils.git /var/lib/mock/f45-build-42199-791/root/chroot_tmpdir/scmroot/rust-gstreamer-pbutils
Cloning into '/var/lib/mock/f45-build-42199-791/root/chroot_tmpdir/scmroot/rust-gstreamer-pbutils'...
$ git fetch origin 9bcaa8b2ebbc53b59d948e89510f4209571fe4e3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gstreamer-pbutils
 * [new ref]         9bcaa8b2ebbc53b59d948e89510f4209571fe4e3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9bcaa8b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild