$ git clone -n https://src.fedoraproject.org/rpms/vlc.git /var/lib/mock/f40-build-1922799-25101/root/chroot_tmpdir/scmroot/vlc
Cloning into '/var/lib/mock/f40-build-1922799-25101/root/chroot_tmpdir/scmroot/vlc'...
$ git fetch origin 50c8c3bc9f298630b17a598fb306456d50ec72c9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vlc
 * [new ref]         50c8c3bc9f298630b17a598fb306456d50ec72c9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 50c8c3b Enable RDP access plugin