Fix multi-line type-alias tuple definitions

Somehow missed it when reworking tuples. We need to allow the new
  'NewLineLeftParen' token in this situation as well. Especially because
  this is what the formatter outputs.

crates/aiken-lang/src/parser.rs

@@ -1388,7 +1388,10 @@ pub fn type_parser() -> impl Parser<Token, ast::Annotation, Error = ParseError>
                 .separated_by(just(Token::Comma))
                 .at_least(2)
                 .allow_trailing()
-                .delimited_by(just(Token::LeftParen), just(Token::RightParen))
+                .delimited_by(
+                    choice((just(Token::LeftParen), just(Token::NewLineLeftParen))),
+                    just(Token::RightParen),
+                )
                 .map_with_span(|elems, span| ast::Annotation::Tuple {
                     location: span,
                     elems,

crates/aiken-lang/src/tests/parser.rs

@@ -1911,3 +1911,40 @@ fn function_ambiguous_sequence() {
         ],
     )
 }
+
+#[test]
+fn tuple_type_alias() {
+    let code = indoc! {r#"
+          type RoyaltyToken =
+            (PolicyId, AssetName)
+        "#};
+
+    assert_definitions(
+        code,
+        vec![ast::UntypedDefinition::TypeAlias(TypeAlias {
+            alias: "RoyaltyToken".to_string(),
+            annotation: ast::Annotation::Tuple {
+                location: Span::new((), 22..43),
+                elems: vec![
+                    ast::Annotation::Constructor {
+                        location: Span::new((), 23..31),
+                        module: None,
+                        name: "PolicyId".to_string(),
+                        arguments: vec![],
+                    },
+                    ast::Annotation::Constructor {
+                        location: Span::new((), 33..42),
+                        module: None,
+                        name: "AssetName".to_string(),
+                        arguments: vec![],
+                    },
+                ],
+            },
+            doc: None,
+            location: Span::new((), 0..43),
+            parameters: vec![],
+            public: false,
+            tipo: (),
+        })],
+    )
+}