Fix utility meter restore state

[dgomes]

Breaking change

Proposed change

Checks restored value is a number

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
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Additional information

• This PR fixes or closes issue: fixes Utility_meter sensor fails during Homeassistant startup on 'None' value #63874
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• Link to documentation pull request:

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[MartinHjelmare]

Why does the user has a string "None" stored for this attribute? We should probably fix that if there's some code that allows that.

[dgomes]

Why does the user has a string "None" stored for this attribute? We should probably fix that if there's some code that allows that.

This is an extreme edge case, moving backwards in time:

• Last period is "None" when restored
• Last period is None when reset happens and the current state is None
• state is None when the sensor is created and hasn't received any status update from the source sensor yet (first update is detected using state = None)

[dgomes]

last commit might solve the root cause, but will not address existing installs

[dgomes]

increased coverage to 100%

[MartinHjelmare]

Thanks!