$ git clone -n http://git.inferitos.ru/rpms/ffmpeg /var/lib/mock/inferit-8_10-extras-build-54329-115166/root/chroot_tmpdir/scmroot/ffmpeg
Cloning into '/var/lib/mock/inferit-8_10-extras-build-54329-115166/root/chroot_tmpdir/scmroot/ffmpeg'...
$ git fetch origin changed/i8cr/ffmpeg-4.2.10-1.el8:KOJI_FETCH_HEAD
From http://git.inferitos.ru/rpms/ffmpeg
 * [new tag]         changed/i8cr/ffmpeg-4.2.10-1.el8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0764f12 import ffmpeg-4.2.10-1.el8