$ git clone -n https://src.fedoraproject.org/rpms/gstreamer1-plugin-libav.git /var/lib/mock/f42-build-865428-173104/root/chroot_tmpdir/scmroot/gstreamer1-plugin-libav
Cloning into '/var/lib/mock/f42-build-865428-173104/root/chroot_tmpdir/scmroot/gstreamer1-plugin-libav'...
$ git fetch origin 36b5882879cd69d5674eb42c439dc7124cce797e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gstreamer1-plugin-libav
 * [new ref]         36b5882879cd69d5674eb42c439dc7124cce797e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 36b5882 1.24.11