fix: disabled Choice binding shortcut_key

[weiduhuo]

What is the problem that this PR addresses?

When defining a Choice type option with simultaneously setting the shortcut_key attribute to str type and setting the
disabled attribute to be not None, there is an unexpected ability that we can interact with this option using keyboard shortcuts.

example:

import questionary
from questionary import Choice

options = [
    Choice("One", disabled=True),
    Choice("Three", shortcut_key="3", disabled=True),
    Choice("Two"),
    Choice("Four"),
]
questionary.select("Title: ", options, use_shortcuts=True).ask()

How did you solve it?

I cancel the disabled choice binding the key.

Checklist

• I have read the Contributor's Guide.
• I will check that all automated PR checks pass before the PR gets reviewed.

[kiancross]

Thanks, looks good to me. Can you force-push the commit to re-trigger the CI?