Remove last_reset attribute and set state class to total_increasing for wemo energy sensors

[emontnemery]

Proposed change

Remove last_reset attribute from and set state class to total_increasing for wemo energy sensors

Background: #54755

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)
• Breaking change (fix/feature causing existing functionality to break)
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• This PR fixes or closes issue: fixes #
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[probot-home-assistant]

Hey there @esev, mind taking a look at this pull request as it has been labeled with an integration (wemo) you are listed as a code owner for? Thanks!
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[emontnemery]

@esev I'm a bit perplexed by the unit conversion for the energy sensor, is the sensor's native unit mWs (milliwatt-second)?

[frenck]

The change itself looks good (besides the above question)

[esev]

@esev I'm a bit perplexed by the unit conversion for the energy sensor, is the sensor's native unit mWs (milliwatt-second)?

Yes, that is correct. Just double-checked since this logic predates when I became involved with the project. According to one of my Wemo Insights, a computer that uses an average of about about 135 watts consumed 0.47 kWh over 3.5 hours. So it does seem to confirm that the conversion is correct and the device is reporting in mWs.