Add a couple more postgres quarter identity tests

Author: georgesittas

tests/dialects/test_postgres.py

@@ -31,6 +31,8 @@ def test_postgres(self):
         self.assertIsInstance(expr, exp.Alter)
         self.assertEqual(expr.sql(dialect="postgres"), alter_table_only)
 
+        self.validate_identity("SELECT EXTRACT(QUARTER FROM CAST('2025-04-26' AS DATE))")
+        self.validate_identity("SELECT DATE_TRUNC('QUARTER', CAST('2025-04-26' AS DATE))")
         self.validate_identity("STRING_TO_ARRAY('xx~^~yy~^~zz', '~^~', 'yy')")
         self.validate_identity("SELECT x FROM t WHERE CAST($1 AS TEXT) = 'ok'")
         self.validate_identity("SELECT * FROM t TABLESAMPLE SYSTEM (50) REPEATABLE (55)")