Hi, this is what I did.

1: Added a file in .github/workflows/ci.yml

name: Code Quality and Ex Unit Tests

on: [pull_request]

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
    - uses: actions/setup-elixir@v1
      with:
        otp-version: '23.0'
        elixir-version: '1.11.1'
    - name: Install Dependencies
      run: |
        mix local.rebar --force
        mix local.hex --force
        mix deps.get
    - name: credo
      uses: red-shirts/reviewdog-action-credo@v1
      with:
        github_token: ${{ secrets.ghactions }}
        reporter: github-pr-review

it gave me this error.

Run red-shirts/reviewdog-action-credo@v1
  with:
    github_token: ***
    reporter: github-pr-review
    level: error
/usr/bin/docker run --name 7fe9c421da50be8a228f67077_4634b0 --label 179394 --workdir /github/workspace --rm -e INPUT_GITHUB_TOKEN -e INPUT_REPORTER -e INPUT_LEVEL -e HOME -e GITHUB_JOB -e GITHUB_REF -e GITHUB_SHA -e GITHUB_REPOSITORY -e GITHUB_REPOSITORY_OWNER -e GITHUB_RUN_ID -e GITHUB_RUN_NUMBER -e GITHUB_RETENTION_DAYS -e GITHUB_ACTOR -e GITHUB_WORKFLOW -e GITHUB_HEAD_REF -e GITHUB_BASE_REF -e GITHUB_EVENT_NAME -e GITHUB_SERVER_URL -e GITHUB_API_URL -e GITHUB_GRAPHQL_URL -e GITHUB_WORKSPACE -e GITHUB_ACTION -e GITHUB_EVENT_PATH -e GITHUB_ACTION_REPOSITORY -e GITHUB_ACTION_REF -e GITHUB_PATH -e GITHUB_ENV -e RUNNER_OS -e RUNNER_TOOL_CACHE -e RUNNER_TEMP -e RUNNER_WORKSPACE -e ACTIONS_RUNTIME_URL -e ACTIONS_RUNTIME_TOKEN -e ACTIONS_CACHE_URL -e GITHUB_ACTIONS=true -e CI=true -v "/var/run/docker.sock":"/var/run/docker.sock" -v "/home/runner/work/_temp/_github_home":"/github/home" -v "/home/runner/work/_temp/_github_workflow":"/github/workflow" -v "/home/runner/work/_temp/_runner_file_commands":"/github/file_commands" -v "/home/runner/work/evercam-server2/evercam-server2":"/github/workspace" 179394:2906b797fe9c421da50be8a228f67077  "***" "error" "github-pr-review"
** (Mix) Could not find an SCM for dependency :bcrypt_elixir from EvercamMedia.Mixfile