Call Google Assistant SDK service using async_add_executor_job

[tronikos]

Breaking change

Proposed change

The assist function that calls Google Assistant SDK service is non async so it's blocking the main thread for several seconds making Home Assistant unresponsive. Call it with async_add_executor_job to prevent that.

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 Async issue on send text command #117188
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
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[PeteRager]

Looks good to me.