Add test case for issue 6650

Author: ytmimi

tests/source/issue_6650.rs

@@ -0,0 +1,5 @@
+// rustfmt-style_edition: 2027
+
+fn main() {
+    matches!(stmt, ast::Stmt{kind: ast::StmtKind::MacCall(box ast::MacCallStmt {style : ast::MacStmtStyle::Braces,..}),..})
+}

tests/target/issue_6650.rs

@@ -0,0 +1,15 @@
+// rustfmt-style_edition: 2027
+
+fn main() {
+    matches!(
+        stmt,
+        ast::Stmt {
+            kind:
+                ast::StmtKind::MacCall(box ast::MacCallStmt {
+                    style: ast::MacStmtStyle::Braces,
+                    ..
+                }),
+            ..
+        }
+    )
+}