For pull-request from forked repository, github token doen't have write permission for security reason, so reviewdog couldn't post results with Review API nor Check API.

As an alternative, I found that we can use error and warning logging command to post annotations in GitHub Actions.
https://help.github.com/en/actions/automating-your-workflow-with-github-actions/development-tools-for-github-actions#example-5

It doesn't require GitHub token, so we can support it even for PR from forked repository!

I created go-actions-toolkit and we can use Error and Warning function.

Related: https://github.com/actions/toolkit/blob/master/docs/problem-matchers.md
We may want to consider to disable Problem Matchers as it could conflict with reviewdog reports.