Cloud: Expose if google is registered in status + check on login

[bramkragten]

Proposed change

This adds information if Google Assistant is setup, so the frontend can handle that correctly.
We also check if Google Assistant was setup when you login to your Cloud account, and activate it.

Related: #48233

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• Breaking change (fix/feature causing existing functionality to break)
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[probot-home-assistant]

Hey there @home-assistant/cloud, mind taking a look at this pull request as its been labeled with an integration (cloud) you are listed as a codeowner for? Thanks!
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