Drop support for fan speeds and support reverse

[elupus]

Breaking change

• Requires resync of google assysten devices since we no longer expose fan speeds. Ask your google device to "Sync my devices" or trigger update via google_assistant.request_sync service.

Proposed change

This change will drop support for the legacy fan speeds. The google docs is a bit unclear as to if it is a supported state to have both fanspeeds and percentages. So let's only support percentages since we have issue's where google still call the legacy services.

Also add support for fan reversion service that we claimed to support, but really didn't.

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)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR is realted to: Fan speed service is still called instead of speed percentage with Google Assistant #52637

Checklist

• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.

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