message: Remove MissingHttpStatusCode
diff: @@ -74,10 +74,6 @@ impl std::error::Error for RequestExtensionNotFoundRejection {}
  /// into an HTTP response.
  #[derive(Debug, Display)]
  pub enum ResponseRejection {
  - /// Used when `httpResponseCode` targets an optional member, and the service implementer sets
  - /// it to `None`.
  - MissingHttpStatusCode,
  -
  /// Used when the service implementer provides an integer outside the 100-999 range for a
  /// member targeted by `httpResponseCode`.
  InvalidHttpStatusCode,
  