Update spotify.md (music-assistant#181)

* Update spotify.md

* Update docs/music-providers/spotify.md

Co-authored-by: OzGav <gavnosp@hotmail.com>

---------

Co-authored-by: OzGav <gavnosp@hotmail.com>

docs/music-providers/spotify.md

@@ -26,6 +26,9 @@ Music Assistant has full support for Spotify media listing and playback.
 - Due to restrictions with Spotify's API, only Spotify Premium accounts are supported (including Duo and Family). Free accounts will not work
 - When using a personal ClientID, automatically generated playlists such as "Discover Weekly" and radio mode will no longer work
 
+!!! note 
+    Official "by Spotify" playlists are not available when using a personal ClientID for authentification.
+
 ## Not yet supported
 
 - Podcasts support ([see this feature request](https://github.com/music-assistant/hass-music-assistant/discussions/429))