Allow modbus negative min/max value.

[janiversen]

Breaking change

Proposed change

When changing to the standard HA validators, the sensor min/max value was limited to a positive int, this is wrong, and corrected.

Test added to avoid regressions.

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 #
  fixes Modbus sensor min_value only allows positive values #109981
• This PR is related to issue:
• Link to documentation pull request:

Checklist

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