Wrong warning shown if `pyproject.toml` found

```
Warning message:
In poetry_config(required_module) :
  This project appears to use Poetry for Python dependency management.
However, the 'poetry' command line tool is not available.
reticulate will be unable to activate this project.
Please ensure that 'poetry' is available on the PATH.
```

This warning is emitted incorrectly in projects that use `uv`, not `poetry` for Python env management.