feat: github actions extension linter-ignore file and ignore settings

[justinthelaw]

Is your feature request related to a problem? Please describe.

In certain GitHub actions, deprecated fields or configurations that are caught by the GitHub actions VSCode extension's linter do still work or exist in certain versions of a GitHub action.

For example, in the screenshot below, the command: manifest configuration in Google's release-please GitHub action does still function, but GitHub actions VSCode extension still considers this an error.

Describe the solution you'd like

I want to be able to add a new comment OR surrounding comments OR a VSCode extension settings file (local to workspace, directory, or user) that will suppress the GitHub actions VSCode extension's linter from highlighting an error.

E.g., adding // gh-actions-ignore to a line suppresses the linter, OR adding a .githubactionsignore file will allow certain files to go unread by the extension (similar to .gitignore), OR a general regex filter in the extensions' VSCode settings

Additional context

N/A

[btrautmann]

In our use case, we're using string interpolation to get at a secret, which obviously the linter doesn't like. Would love to be able to ignore this.