feat(rlp): add helpful assert message upon client init error (#578)

tests_consume/test_via_rlp.py

@@ -174,7 +174,11 @@ def client(
         client_type=client_type, environment=environment, files=client_files
     )
     timing_data.start_client = time.perf_counter() - t_start
-    assert client is not None
+    error_message = (
+        f"Unable to connect to the client container ({client_type.name}) via Hive during test "
+        "setup. Check the client or Hive server logs for more information."
+    )
+    assert client is not None, error_message
     yield client
     t_start = time.perf_counter()
     client.stop()