tests/cpydiff: Indent workaround code snippet so it formats correctly.

tests/cpydiff/types_exception_subclassinit.py

@@ -4,7 +4,7 @@ description: Exception.__init__ method does not exist.
 cause: Subclassing native classes is not fully supported in MicroPython.
 workaround: Call using ``super()`` instead::
 
-class A(Exception):
+    class A(Exception):
         def __init__(self):
             super().__init__()
 """