Bump lcn-frontend to 0.2.1

[alengwenus]

Proposed change

Bump frontend panel for LCN to newest version.
Enables the possibility to set up new switches introduced in #127731

Release notes: https://github.com/alengwenus/lcn-frontend/releases
Code changes: alengwenus/lcn-frontend@0.2.0...0.2.1

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)
• Code quality improvements to existing code or addition of tests

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• This PR fixes or closes issue: fixes #
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[frenck]

Thanks, @alengwenus 👍

../Frenck