shellcheck for Jenkinsfile sh block

usage: jenkinsfile-shellcheck [options]
 -h,--help           usage information
 -i,--input <file1,file2,...>   input files (default: Jenkinsfile)
    --no-expand-gstring         do not expand GString values

 shellcheck options can be written after '--'.
 e.g. groovy jenkinsfile-shellcheck.groovy -- -e SC2154

Required. Must be in form of github_token: ${{ secrets.github_token }}'.

Optional. shellcheck options.

Optional. Report level for reviewdog [info,warning,error]. It's same as -level flag of reviewdog. Default is error.

Reporter of reviewdog command [github-pr-check,github-pr-review]. Default is github-pr-check.

Optional. Tool name to use for reviewdog reporter. Useful when running multiple actions with different config.

Optional. List of folders and files to exclude from checking.

Optional. Filtering mode for the reviewdog command [added, diff_context, file, nofilter]. Default is added.

Optional. Exit code for reviewdog when errors are found [true, false] Default is false.

Optional. Additional reviewdog flags.

name: Reviewdog
on: [pull_request]

jobs:
  jenkinsfile-shellcheck:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v3
    - uses: srz-zumix/jenkinsfile-shellcheck@v1
      with:
        github_token: ${{ secrets.github_token }}
        reporter: github-pr-review
        shellcheck_flags: "--exclude SC2086" # Optional