Bump gcal_sync to 6.0.1

[allenporter]

Proposed change

Bump gcal_sync to 6.0.1

Release notes: https://github.com/allenporter/gcal_sync/releases/tag/6.0.1
Files changed: allenporter/gcal_sync@5.0.0...6.0.1

The motivation is to pull in client side fixes to gracefully handle invalid Google Calendars RRULES #91119 there there is an additional bug in home assistant that also needs to be fixed in a followup PR. The release also contains another change to not leak pydantic exceptions (not caught today in home assistant), wrapping them with a calendar api exception.

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:
• This PR is related to issue: Error fetching Google Calendar data: Invalid recurrence rule in 2023.04.2 #91119
• Link to documentation pull request:

Checklist

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