message: neater serialization
diff: @@ -49,6 +49,7 @@ mod space_separated_scope {
  use serde::{de, Deserialize, Serializer};
  use std::collections::HashSet;
  use std::iter::FromIterator;
  +
  pub(crate) fn deserialize<'de, D>(d: D) -> Result<HashSet<String>, D::Error>
  where
  D: de::Deserializer<'de>,
  @@ -58,7 +59,6 @@ mod space_separated_scope {
  scope
  .split_whitespace()
  .map(|x| x.to_owned())
  - .collect::<Vec<String>>(),
  ))
  }
  @@ -66,16 +66,10 @@ mod space_separated_scope {
  where
  S: Serializer,
  {
  - s.serialize_str(
  - scope
  - .iter()
  - .map(|x| x.to_owned())
  - .collect::<Vec<String>>()
  - .join(" ")
  - .as_ref(),
  - )
  + s.serialize_str(&Vec::from_iter(scope.clone()).join(" "))
  }
  }
  +
  /// Spotify access token information
  /// [Reference](https://developer.spotify.com/documentation/general/guides/authorization-guide/)
  #[derive(Builder, Clone, Debug, Serialize, Deserialize)]
  