Merge pull request #2374 from tausbn/python-fix-mappingproxytype-fp

Python: Fix non-container FP relating to `MappingProxyType`.

python/ql/test/query-tests/Expressions/general/expressions_test.py

@@ -234,3 +234,11 @@ def func():
     except TypeError:
       return 1
     return 0
+
+# False positive for py/member-test-non-container
+
+# Container wrapped in MappingProxyType
+from types import MappingProxyType
+
+def mpt_arg(d=MappingProxyType({})):
+    return 1 in d