pyfinder cli cannot disable `ignore_unsupported`

[TBBle]

While experimenting with pyfinder, I noticed that ignore_unsupported defaults to True, and lacks any way to override that to false. (I also tried env-var values 0 and FALSE, they didn't disable the option.)

My guess is that it needs a disabling flag defined, e.g., --include-unsupported, i.e. something like

@click.option(
    "--ignore-unsupported/--include-unsupported",
    "--no-unsupported/--unsupported",
    default=True,
    envvar="PYTHONFINDER_IGNORE_UNSUPPORTED",
    help="Ignore unsupported python versions.",
)

---

As a side-note, it also seems to output an extraneous "Please provide a command" if no Python versions are found, possibly due to a missing elif and/or missing ctx.exit(1) after failure output.

Also, the --find, --which, --findall flags should maybe be Feature Switches rather than Boolean Flags, since they are mutually exclusive, or at least should be, since they are processed by an if-elif chain.