Move thread safety check in async_register/async_remove

[bdraco]

Proposed change

Move the thread safety check in the async_register and async_remove path to be sooner so it catches the problem before the service is being registered.

Previously it would catch it when async_fire was called which was confusing to the dev because it would complain about async_fire and not async_register or async_remove.

RuntimeError: Detected that custom integration 'scaletest' calls async_register from a thread at custom_components/scaletest/__init__.py, line 18: hass.services.async_register(DOMAIN, "not_safe", lambda x : None). Please report it to the author of the 'scaletest' custom integration.

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:
• Link to documentation pull request:

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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[bdraco]

thanks