Ensure Tile timestamps are reported as UTC

[bachya]

Proposed change

SSIA

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 Tile integration last timestamp appears to have some timezone handling issues #106009
• This PR is related to issue: N/A
• Link to documentation pull request: N/A

Checklist

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