Add sample test for assertions with messages

tests/_exception.py

@@ -41,4 +41,11 @@ def f1():
 try:
     f1()
 except KeyError:
-    print("PASS 04")
+    print("PASS 04")
+
+
+assert True, "Msg"
+try:
+    assert False, "Msg"
+except AssertionError:
+    print("PASS 05")