Remove deprecated YAML configuration from MJPEG Camera

[frenck]

Breaking change

The previously deprecated YAML configuration of the MJPEG integration has been removed.

MJPEG is now configured via the UI, any existing YAML configuration has been imported in previous releases and can now be safely removed from your YAML configuration files.

Proposed change

Removes the deprecated YAML importer from the MJPEG integration.

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

Additional information

• This PR fixes or closes issue: fixes #
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• Link to documentation pull request:

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[davet2001]

Looks good to me :)