flutter-docker-image/script/createGitTag.js

module.exports = async ({ core, context, github }) => {
  const { OLD_FLUTTER_VERSION, NEW_FLUTTER_VERSION } = process.env

  if (!OLD_FLUTTER_VERSION) {
    core.setFailed('Environment variable OLD_FLUTTER_VERSION is required.')
  }

  if (!NEW_FLUTTER_VERSION) {
    core.setFailed('Environment variable NEW_FLUTTER_VERSION is required.')
  }

  if (OLD_FLUTTER_VERSION === NEW_FLUTTER_VERSION) {
    return
  }

  // Create a git tag using the GitHub API instead of the git client to skip SSH/GPG key setup.
  github.rest.git.createRef({
    owner: context.repo.owner,
    repo: context.repo.repo,
    ref: `refs/tags/${NEW_FLUTTER_VERSION}`,
    sha: context.sha,
  })
}