Update python/ql/src/Classes/SubclassShadowing/examples/SubclassShadowingBad.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: joefarebrother

python/ql/src/Classes/SubclassShadowing/examples/SubclassShadowingBad.py

@@ -2,7 +2,7 @@ class A:
     def __init__(self):
         self._foo = 3
 
-class B:
+class B(A):
     # BAD: _foo is shadowed by attribute A._foo
     def _foo(self):
         return 2