# What does this PR do?
This is to avoid errors like the following when running inference
integration tests:
```
ERROR tests/integration/inference/test_text_inference.py::test_text_completion_stop_sequence[txt=8B-inference:completion:stop_sequence] - llama_stack.distribution.stack.EnvVarError: Environment variable 'VLLM_URL' not set or empty at providers.inference[0].config.url
```
It's also good to have a default, which is consistent with vLLM API
server.
## Test Plan
Integration tests can run without the error above.
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Signed-off-by: Yuan Tang <terrytangyuan@gmail.com>
dce9a24a6c