Add support to Google Calendar for Web auth credentials

[allenporter]

Proposed change

Add support to Google Calendar for Web auth credentials. This means that in the future all google integrations that work on personal user data can use the same credentials, opening up the possibility for sharing credentials across integrations. This is follow up discussion from #102629 (comment)

The approach is to try attempt device auth and if it fails with invalid_client then attempt web auth. This requires minimal changes to short circuit and use the default web auth behavior with a couple of overrides in a few places in the config flow and auth implementation.

This was manually tested with web auth credentials.

We can explore actually sharing application credentials in the future. One challenge, though, is that it is difficult to tell the credential type without actually attempting to use them. For now, we record the credential type in the config entry -- this has no use now, but may be needed later to know what type of credential we have.

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: Update google calendar instructions to recommend Web Auth home-assistant.io#29792

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
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• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

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[MartinHjelmare]

Thanks!