Options are required in select selector if custom_value is False

[raman325]

Proposed change

As mentioned here: #68952 (comment)

It only makes sense to not provide options when custom_value is True, and I think it's better to require that at least one option is included if options is specified. This preserves the original behavior when custom_value is False but allows options to not be provided when custom_value is True.

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• This PR fixes or closes issue: fixes #
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• Link to documentation pull request: Update docs for select selector home-assistant.io#22207

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[probot-home-assistant]

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[dgomes]

CC @emontnemery

[frenck]

As selectors are now usable by the backend: If the backend doesn't have an option to present (whatever the reason), it would break instead of listing no options.

That is why its OK to have an empty list.