$ git clone -n https://src.fedoraproject.org/rpms/rust-gstreamer-video.git /var/lib/mock/f40-build-2268850-54749/root/chroot_tmpdir/scmroot/rust-gstreamer-video
Cloning into '/var/lib/mock/f40-build-2268850-54749/root/chroot_tmpdir/scmroot/rust-gstreamer-video'...
$ git fetch origin b43b6eb12efdc6686127c00c74c3b4851c603be0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gstreamer-video
 * [new ref]         b43b6eb12efdc6686127c00c74c3b4851c603be0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b43b6eb Update to version 0.21.2; Fixes RHBZ#2249242