bpo-41520: Fix second codeop regression (GH-21848)

* bpo-41520: Fix second codeop repression

Fix the repression introduced by the initial regression fix.
diff --git a/Lib/test/test_codeop.py b/Lib/test/test_codeop.py
index 7984e5f..45d0a7d 100644
--- a/Lib/test/test_codeop.py
+++ b/Lib/test/test_codeop.py
@@ -307,14 +307,17 @@
 
     def test_warning(self):
         # Test that the warning is only returned once.
-        with warnings_helper.check_warnings((".*literal", SyntaxWarning)) as w:
-            compile_command("0 is 0")
-            self.assertEqual(len(w.warnings), 1)
+        with warnings_helper.check_warnings(
+                (".*literal", SyntaxWarning),
+                (".*invalid", DeprecationWarning),
+                ) as w:
+            compile_command(r"'\e' is 0")
+            self.assertEqual(len(w.warnings), 2)
 
         # bpo-41520: check SyntaxWarning treated as an SyntaxError
-        with self.assertRaises(SyntaxError):
+        with warnings.catch_warnings(), self.assertRaises(SyntaxError):
             warnings.simplefilter('error', SyntaxWarning)
-            compile_command('1 is 1\n', symbol='exec')
+            compile_command('1 is 1', symbol='exec')
 
 
 if __name__ == "__main__":