Automate supervisor & landing-page release

[wendevlin]

Proposed change

• add release workflow jobs
  • release supervisor
  • release landing-page

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 #
• 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

[frenck]

IMHO this should be done the other way around.

Landingpage should be responsible for itself and care about its own; this logic should thus live in the landing page repo, not frontend repo.