Make UniFi bandwidth sensors be about current transfer rather than total transfer

[Kane610]

Breaking change

Proposed change

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• This PR fixes or closes issue: fixes unifi: bandwidth entity is actually accumulated transfer #56462
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[austinmroczek]

LGTM

[emontnemery]

Looks good, but we should consider renaming the *BandwidthSensor classes since the sensors measure MB, not MB/s.