Reduce modbus validator for "swap" (remove special handling)

[janiversen]

Breaking change

Proposed change

because "swap: None" is no longer allowed, it is possible to handle swap as other parameters.

With this validation of all standard parameters are tablelized.

Type of change

• Dependency upgrade
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• Breaking change (fix/feature causing existing functionality to break)
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• This PR fixes or closes issue: fixes #
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