Fix incorrect storage usage per camera (#16825)

[toperichvania]

Proposed change

This increases the decimal precision in round() for better accuracy in system metrics.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code
• Documentation Update

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue: [Bug]: System Metrics Storage not showing correct usage per camera #16825

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.
• The code has been formatted using Ruff (ruff format frigate)

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