Update opentherm_gw.binary_sensor to use entity_description

[mvn23]

Proposed change

Update opentherm_gw to use entity descriptions for its binary_sensor entities.
Partial fix for #119271

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue: temp. sensor group fails during boot #119271
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
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• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.

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[joostlek]

I think this integration has a lot of potential to make use of new features within home assistant so we can maintain a nice consistent user experience between integrations, if you have questions about this or want to think with me about it, feel free to hmu on discord :)

[joostlek]

(Oh and sorry for reviewing before you put it as ready, I like revamping integrations)

[mvn23]

(Oh and sorry for reviewing before you put it as ready, I like revamping integrations)

No problem, I appreciate the feedback. I'm planning a few follow-up PRs already to take care of the rest of the integration, can I tag you in those as well later on?

[joostlek]

We usually don't like tagging and we like to keep PRs with a mindset of "anyone can pick them up". But I will see them anyway as I check all PRs :)