change schema -> dataset_schema for register_dataset api (#443)

# What does this PR do?

- API updates: change schema to dataset_schema for register_dataset for
resolving pydantic naming conflict
- Note: this OpenAPI update will be synced with
llama-stack-client-python SDK.

cc @dineshyv 

## Test Plan

```
pytest -v -s -m meta_reference_eval_together_inference_huggingface_datasetio eval/test_eval.py
```

## Sources

Please link relevant resources if necessary.


## Before submitting

- [ ] This PR fixes a typo or improves the docs (you can dismiss the
other checks if that's the case).
- [ ] Ran pre-commit to handle lint / formatting issues.
- [ ] Read the [contributor
guideline](https://github.com/meta-llama/llama-stack/blob/main/CONTRIBUTING.md),
      Pull Request section?
- [ ] Updated relevant documentation.
- [ ] Wrote necessary unit or integration tests.

llama_stack/apis/datasets/datasets.py

@@ -49,7 +49,7 @@ class Datasets(Protocol):
     async def register_dataset(
         self,
         dataset_id: str,
-        schema: Dict[str, ParamType],
+        dataset_schema: Dict[str, ParamType],
         url: URL,
         provider_dataset_id: Optional[str] = None,
         provider_id: Optional[str] = None,

llama_stack/distribution/routers/routing_tables.py

@@ -310,7 +310,7 @@ class DatasetsRoutingTable(CommonRoutingTableImpl, Datasets):
     async def register_dataset(
         self,
         dataset_id: str,
-        schema: Dict[str, ParamType],
+        dataset_schema: Dict[str, ParamType],
         url: URL,
         provider_dataset_id: Optional[str] = None,
         provider_id: Optional[str] = None,
@@ -332,7 +332,7 @@ class DatasetsRoutingTable(CommonRoutingTableImpl, Datasets):
             identifier=dataset_id,
             provider_resource_id=provider_dataset_id,
             provider_id=provider_id,
-            dataset_schema=schema,
+            dataset_schema=dataset_schema,
             url=url,
             metadata=metadata,
         )

llama_stack/providers/tests/datasetio/test_datasetio.py

@@ -57,7 +57,7 @@ async def register_dataset(
 
     await datasets_impl.register_dataset(
         dataset_id=dataset_id,
-        schema=dataset_schema,
+        dataset_schema=dataset_schema,
         url=URL(uri=test_url),
     )
 

llama_stack/providers/tests/eval/test_eval.py

@@ -163,7 +163,7 @@ class Testeval:
 
         await datasets_impl.register_dataset(
             dataset_id="mmlu",
-            schema={
+            dataset_schema={
                 "input_query": StringType(),
                 "expected_answer": StringType(),
                 "chat_completion_input": ChatCompletionInputType(),