Set default values for required and disabled for labeled slider

[silamon]

Proposed change

A material web package regression causes the slider to be disabled if disabled is set to undefined. Unfortunately, that's the case for the components that use ha-labeled-slider. This sets a default value.

(If possible, please tag for beta release)

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (thank you!)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example configuration

Additional information

• This PR fixes or closes issue: fixes RGBW light sliders disabled #19209
• This PR is related to issue or discussion:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io