Fix handling undecoded mqtt sensor payloads

[jbouwh]

Proposed change

When an MQTT sensor update is decoded, and is in a bytes format we should not apply a string wrapper when we process it. Instead we should log a warning and stop processing the update.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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Additional information

• This PR fixes or closes issue: fixes MQTT Exception raised while updating state of sensor BatteryStateAttribute/level' with payload: b'88' #118629
• This PR is related to issue:
• Link to documentation pull request:

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[home-assistant]

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

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[jbouwh]

Thanks!