remove mopidy musicbox (unmaintained since 2020) (#3769)

- ref. https://github.com/awesome-selfhosted/awesome-selfhosted/issues/3558
- WARNING:awesome_lint.py: Mopidy MusicBox: last updated -1041 days, 9:56:58.110949 ago, older than 365 days

README.md

@@ -1222,7 +1222,6 @@ _See also: [List of streaming media systems - Wikipedia](https://en.wikipedia.or
 - [LMS](https://github.com/epoupon/lms) - Access your self-hosted music using a web interface. `GPL-3.0` `C++`
 - [Maloja](https://github.com/krateng/maloja) - Self-hosted music scrobble database, alternative to Last.fm. ([Demo](https://maloja.krateng.ch/)) `GPL-3.0` `Python/Docker`
 - [moOde Audio](https://moodeaudio.org/) - Audiophile-quality music playback for the wonderful Raspberry Pi family of single board computers. ([Source Code](https://github.com/moode-player/moode)) `GPL-3.0` `PHP`
-- [Mopidy MusicBox](https://github.com/pimusicbox/mopidy-musicbox-webclient) - Web Client for Mopidy Music Server. `Apache-2.0` `HTML5`
 - [Mopidy](https://docs.mopidy.com/) - Extensible music server. Offers a superset of the mpd API, as well as integration with 3rd party services like Spotify, SoundCloud etc. ([Source Code](https://github.com/mopidy/mopidy)) `Apache-2.0` `Python`
 - [mpd](https://www.musicpd.org/) - Daemon to remotely play music, stream music, handle and organize playlists. Many clients available. ([Source Code](https://github.com/MusicPlayerDaemon/MPD), [Clients](https://www.musicpd.org/clients/)) `GPL-2.0` `C++`
 - [mStream](https://mstream.io/) - Music streaming server with GUI management tools. Runs on Mac, Windows, and Linux. ([Source Code](https://github.com/IrosTheBeggar/mStream)) `GPL-2.0` `Nodejs`