message: Add debug_assert for mistake in playlist creation
diff: @@ -229,6 +229,12 @@ pub trait OAuthClient: BaseClient {
  collaborative: Option<bool>,
  description: Option<&str>,
  ) -> ClientResult<FullPlaylist> {
  + debug_assert!(
  + !(collaborative.unwrap_or(false) && public.unwrap_or(false)),
  + "To create a collaborative playlist you must also set public to \
  + false. See the reference for more information."
  + );
  +
  let params = build_json! {
  "name": name,
  optional "public": public,
  