Allow multiple sections

[gjohansson-ST]

Proposed change

Allow us to use multiple sections e.g. the user can add/remove sections from the same configuration.
See frontend PR how it would be displayed for the user.

Frontend: home-assistant/frontend#22965
Dev docs: home-assistant/developers.home-assistant#2471

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• Dependency upgrade
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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @home-assistant/core, mind taking a look at this pull request as it has been labeled with an integration (kitchen_sink) you are listed as a code owner for? Thanks!

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[MartinHjelmare]

Please provide an overview of use cases and existing integrations that can use the new selector config, besides the compensation integration.

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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