fix mock session to raise status

Author: MHHukiewitz

tests/unit/test_asynchronous_get.py

@@ -23,6 +23,9 @@ async def __aexit__(self, exc_type, exc_val, exc_tb):
         def status(self):
             return 200
 
+        def raise_for_status(self):
+            ...
+
         async def json(self):
             return get_return_value