Don't combine old and new value on scene update

[bramkragten]

Proposed change

When you would remove a key from the scene config in the UI, it would be merged back in, in the backend. This solves that, the new config is always the complete config and not a partial one. So no need to merge with the old value.

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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[spacegaier]

Confirmed it fixes the issue.