$ git clone -n https://src.fedoraproject.org/rpms/rust-gstreamer.git /var/lib/mock/f42-build-side-1-3584342-46893/root/chroot_tmpdir/scmroot/rust-gstreamer
Cloning into '/var/lib/mock/f42-build-side-1-3584342-46893/root/chroot_tmpdir/scmroot/rust-gstreamer'...
$ git fetch origin bf146d077c2c0def83b9e3b7a0d094a77a202078:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gstreamer
 * [new ref]         bf146d077c2c0def83b9e3b7a0d094a77a202078 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bf146d0 Update to version 0.23.6; Fixes RHBZ#2365894