Jekyll starter workflow build failed with theme

I chose Jekyll theme in GitHub Pages repository settings.
Then I used jekyll starter workflow and my build doesn’t work.

My workflow file:

name: Jekyll site CI

on:
  push:
    branches: [ master ]
  pull_request:
    branches: [ master ]

jobs:
  build:

    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
    - name: Build the site in the jekyll/builder container
      run: |
        docker run \
        -v ${{ github.workspace }}:/srv/jekyll -v ${{ github.workspace }}/_site:/srv/jekyll/_site \
        jekyll/builder:latest /bin/bash -c "chmod 777 /srv/jekyll && jekyll build --future"

Error log:

                    ------------------------------------------------
      Jekyll 4.1.0   Please append `--trace` to the `build` command 
                     for any additional information or backtrace. 
                    ------------------------------------------------
/usr/gem/gems/jekyll-4.1.0/lib/jekyll/theme.rb:82:in `rescue in gemspec': The jekyll-theme-slate theme could not be found. (Jekyll::Errors::MissingDependencyException)

This build failed with any selected theme.
This build OK without theme, when _config.yml is empty.

This is a normal working or bug?

Hi @danilanekrasov,

Glad to see you in Github Community Forum!

I cannot reproduce the error on my side, could you please share a sample repo for further investigation?

Thanks