fix(smithy-aws-core): omit Result wrapper for empty awsQuery output (#714)

* fix(smithy-aws-core): omit Result wrapper for empty awsQuery output

* Add changelog entry

* Remove unit test of the fix

Author: Alan4506

packages/smithy-aws-core/.changes/next-release/smithy-aws-core-bugfix-05435b3fb9a54b86b4ebb4d61b0d13ae.json

@@ -0,0 +1,4 @@
+{
+  "type": "bugfix",
+  "description": "Fixed awsQuery response deserialization for operations with no output members."
+}

packages/smithy-aws-core/src/smithy_aws_core/aio/protocols.py

@@ -364,10 +364,14 @@ def _action_name(
     def _response_wrapper_elements(
         self,
         operation: APIOperation[SerializeableShape, DeserializeableShape],
-    ) -> tuple[str, str]:
+    ) -> tuple[str, ...]:
+        name = operation.schema.id.name
+        # Operations with no output members will omit the <OpResult> element.
+        if not operation.output_schema.members:
+            return (f"{name}Response",)
         return (
-            f"{operation.schema.id.name}Response",
-            f"{operation.schema.id.name}Result",
+            f"{name}Response",
+            f"{name}Result",
         )
 
     def _error_wrapper_elements(self) -> tuple[str, ...]: