There is no formatter for 'github-actions-workflow'

**Describe the bug**
A clear and concise description of what the bug is.

**Expected behavior**
I would expect formatting to 'just work' and also to have documentation about how to configure it

**Extension Version**
`v0.25.7`

**Additional context**
Add any other context about the problem here.

Start by reviewing the discussion on issue #195 and reproducing the missing formatting behavior in the GitHub Actions VS Code extension using the attached example. Identify the extension's existing formatting and configuration entry points, then define done as working formatting for github-actions-workflow plus documentation explaining how to configure it.

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