Log Message:
musicpd: update to 0.23.6.

ver 0.23.6 (2022/03/14)
* protocol
  - support filename "cover.webp" for "albumart" command
  - support "readcomments" and "readpicture" on CUE tracks
* decoder
  - ffmpeg: fix end-of-file check (update stuck at empty files)
  - opus: fix "readpicture" on Opus files
* output
  - pipewire: fix crash bug if setting volume before playback starts
  - wasapi: fix resume after pause