Add config flow for template binary sensor

[emontnemery]

Proposed change

Add config flow for template binary sensor:

• The config flow only supports configuring name, state template and device class
• The config flow has preview support enabled

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

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[MartinHjelmare]

Do we test that the config entry creates a state via the platform somewhere, besides the preview?

[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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[emontnemery]

Do we test that the config entry creates a state via the platform somewhere, besides the preview?

Yes, it's tested in tests/components/template/test_config_flow.py::test_config_flow

However, I think the part which tests the state should be moved to the respective platform test, tests/components/template/test_binary_sensor.py::test_setup_from_config_entry or something like that.