message: Add Source as a CustomerSource, add default_source to CustomerParams
diff: @@ -14,6 +14,7 @@ pub struct CustomerShippingDetails {
  #[derive(Serialize)]
  #[serde(untagged)]
  pub enum CustomerSource<'a> {
  + Source(&'a str),
  Token(&'a str),
  Card(CardParams<'a>),
  }
  @@ -28,6 +29,8 @@ pub struct CustomerParams<'a> {
  #[serde(skip_serializing_if = "Option::is_none")]
  pub business_vat_id: Option<&'a str>,
  #[serde(skip_serializing_if = "Option::is_none")]
  + pub default_source: Option<CustomerSource<'a>>,
  + #[serde(skip_serializing_if = "Option::is_none")]
  pub coupon: Option<&'a str>,
  #[serde(skip_serializing_if = "Option::is_none")]
  pub description: Option<&'a str>,
  