$ git clone -n https://src.fedoraproject.org/rpms/ffmpeg.git /var/lib/mock/f41-build-846087-162961/root/chroot_tmpdir/scmroot/ffmpeg
Cloning into '/var/lib/mock/f41-build-846087-162961/root/chroot_tmpdir/scmroot/ffmpeg'...
$ git fetch origin 2612e2ec91e40f76523de881172e52c689b0cebc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ffmpeg
 * [new ref]         2612e2ec91e40f76523de881172e52c689b0cebc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2612e2e Update to 6.1.2