message: Update Source source_type type
diff: @@ -70,7 +70,7 @@ pub struct RedirectParams<'a> {
  pub struct SourceParams<'a> {
  #[serde(rename = "type")]
  #[serde(skip_serializing_if = "Option::is_none")]
  - pub source_type: Option<&'static str>,
  + pub source_type: Option<&'a str>,
  #[serde(skip_serializing_if = "Option::is_none")]
  pub amount: Option<u64>,
  #[serde(skip_serializing_if = "Option::is_none")]
  