Bump ical to 7.0.1 and always use home assistant timezone for local todo dtstart

[allenporter]

Proposed change

Bump ical to 7.0.1 which fixes a few different todo and timezone bugs. Updated to always use home assistant timezone for local todo dtstart to avoid using misconfigured system timezones for dtstart values.

The fixes in 7.0.1 are fixing issues created in 2023.3 that allowed inconsistencies between dates that break the rfc (now auto repaired) and allowed invalid timezones in dstart.

Release notes: https://github.com/allenporter/ical/releases/tag/7.0.1
Changes: allenporter/ical@7.0.0...7.0.1

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 Cannot load todo list after restart #112713, fixes Can't save any new To Do items when system timezone is not valid timezone #112647
• This PR is related to issue:
• Link to documentation pull request:

Checklist

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