This PR bumps the client tests from `google/flan-t5-xxl` to
`meta-llama/Llama-2-7b-chat-hf` to resolve issues when calling the
endpoint and `google/flan-t5-xxl` is not available
run with
```bash
make python-client-tests
clients/python/tests/test_client.py .............. [ 43%]
clients/python/tests/test_errors.py .......... [ 75%]
clients/python/tests/test_inference_api.py ...... [ 93%]
clients/python/tests/test_types.py .. [100%]
```
**note `google/flan-t5-xxl` function is currently unused but still
included in the `conftest.py`
