Handle invalid scale for zwave_js multilevel/meter sensors

[raman325]

Proposed change

With this change, when we get an unknown scale, we just don't set the entity description key or unit and fallback to the metadata.unit value. This is a certification requirement.

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)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR fixes or closes issue: fixes Z-Wave JS: Several entities become unavailable when device sends multilevel sensor report with unknown scale, Certification requirements not fulfilled #92801
• This PR is related to issue:
• Link to documentation pull request:

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Hey there @home-assistant/z-wave, mind taking a look at this pull request as it has been labeled with an integration (zwave_js) you are listed as a code owner for? Thanks!

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[home-assistant]

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