Proposed change

Limit unique_id migration to single platforms during BMW init.

While unique_id is unique inside a platform, the migration script introduced with #121380 is not.
Unfortunately, we have a binary_sensor and a sensor with the same unique_id (before migration), so everytime the component is initialized, the binary sensor gets (wrongly) migrated.

Maybe open:
Clean up entities with wrong unique_id on init. (would love some feedback if this should be done or not)

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR fixes or closes issue: fixes Problems with battery charging binary sensor #131556
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