Fix Sphinx docs build: docstring indentation causing RST parse error

Remove extra indentation on continuation line in oci_genai_fixture
docstring that sphinx-autoapi rendered as a malformed block quote.
Also remove unused Generator return type annotations from OCI
fixtures for consistency with the rest of the file.

Author: fede-kamel

packages/nvidia_nat_test/src/nat/test/plugin.py

@@ -152,7 +152,7 @@ def openai_api_key_fixture(fail_missing: bool):
 
 
 @pytest.fixture(name="oci_nemotron_endpoint", scope='session')
-def oci_nemotron_endpoint_fixture(fail_missing: bool) -> Generator[dict[str, str], None, None]:
+def oci_nemotron_endpoint_fixture(fail_missing: bool):
     """
     Use for integration tests that require an OCI-hosted Nemotron OpenAI-compatible endpoint.
     """
@@ -246,12 +246,12 @@ def azure_openai_keys_fixture(fail_missing: bool):
 
 
 @pytest.fixture(name="oci_genai", scope='session')
-def oci_genai_fixture(fail_missing: bool) -> Generator[dict[str, str], None, None]:
+def oci_genai_fixture(fail_missing: bool):
     """
     Use for integration tests that require OCI Generative AI credentials.
     Required: OCI_COMPARTMENT_ID.
     Optional: OCI_REGION (default: us-chicago-1), OCI_META_MODEL (default: meta.llama-3.3-70b-instruct),
-              OCI_GOOGLE_MODEL (default: google.gemini-2.5-flash).
+    OCI_GOOGLE_MODEL (default: google.gemini-2.5-flash).
     Auth is read from ~/.oci/config using the DEFAULT profile.
     """
     yield require_env_variables(