test(utils): allow /v1/listen in the registry supported_endpoints schema

The deepgram/streaming/* rows added for the Deepgram WebSocket passthrough declare /v1/listen as their endpoint, so the registry validation test needs it in the enum, the same way /vertex_ai/live was added for that passthrough

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

tests/test_litellm/test_utils.py

@@ -945,6 +945,7 @@ def test_aaamodel_prices_and_context_window_json_is_valid():
                             "/v1/audio/speech",
                             "/v1/ocr",
                             "/vertex_ai/live",
+                            "/v1/listen",
                             "/v1beta/interactions",
                         ],
                     },