audio/picard-plugins: Update to snapshot from 2022-02-14

Add DOCS option and install documentation in ${DOCSDIR}.

New plugins:

• submit_isrc (submit ISRCs found in audio files metadata)

Removed plugins:

• videotools (provided formats are non-functional and the is_video() and is_audio() functions are part of Picard)

Additional info can be found at: https://picard.musicbrainz.org/plugins/