chore: test model coverage

Address TestModel coverage issue due to logic structure in _get_output.
This is not introduced by the current PR but was preventing it from
passing coverage checks.

Author: stevenh

pydantic_ai_slim/pydantic_ai/models/test.py

@@ -184,14 +184,14 @@ def _get_output(self, model_request_parameters: ModelRequestParameters) -> _Wrap
 
             if k := output_tool.outer_typed_dict_key:
                 return _WrappedToolOutput({k: self.custom_output_args})
-            else:
-                return _WrappedToolOutput(self.custom_output_args)
+
+            return _WrappedToolOutput(self.custom_output_args)
         elif model_request_parameters.allow_text_output:
             return _WrappedTextOutput(None)
-        elif model_request_parameters.output_tools:
+        elif model_request_parameters.output_tools:  # pragma: no branch
             return _WrappedToolOutput(None)
         else:
-            return _WrappedTextOutput(None)
+            return _WrappedTextOutput(None)  # pragma: no cover
 
     def _node_response(
         self,