Add unique_id and device_info to DSMR entities

[RobBie1221]

Breaking change

Proposed change

This PR adds unique ids and device info to the entities based on the serial id that is read from the energy/gas meter. Additionally, if a gas serial id is missing, don't create the gas meter entities because no gas meter is connected.

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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• This PR fixes or closes issue: fixes #
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[ctalkington]

just a minor tweak

[RobBie1221]

Thanks!