fix(test): adapt QueryResult mock to pass runtime checking

Runtime checking mock objects is an interesting case!
Mock objects rightfully get rejected by runtime type checking,
the solution is to point the mock object's __class__ to the class of
the mocked object.

See beartype/beartype#92.

tests/unit/test_sad_path_get_bindings_from_query_result.py

@@ -4,11 +4,14 @@
 
 import pytest
 
+from SPARQLWrapper.Wrapper import QueryResult
 from rdfproxy.utils.sparql_utils import get_bindings_from_query_result
 
 
 def test_basic_sad_path_get_bindings_from_query_result():
     with mock.patch("SPARQLWrapper.QueryResult") as mock_query_result:
+        mock_query_result.__class__ = QueryResult
+
         mock_query_result.return_value.requestedFormat = "xml"
         exception_message = (
             "Only QueryResult objects with JSON format are currently supported."