Does not handle spaces in options value

[ypresto]

Mediakit::FFmpeg::Options::OutputFileOption.new(
  options: {
    filter_complex: "[0:v][0:a][1:v][1:a] concat=2:v=1:a=1",
    ...

will produce -filter_complex \\[0:v\\]\\[0:a\\]\\[1:v\\]\\[1:a\\] concat\\=2:v\\=1:a\\=1 and it does not quote nor escape space between streams and concat.

[ainame]

nice feedback 👍

[ainame]

This is intended behavior.