Example workflow for using github action's residing in a private repo!

github-private_repo_action.yaml

# To use github actions from a private repo, you can clone the action's private repo locally in the workflow and execute it.
# Below is an example workflow for reference! :)

name: Private Action X

on:
  pull_request:
    branches:
      - master
      - release
     paths:
     - service/**

jobs:
  private:
    name: Private Action X
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v2
      
      # check the private action repo locally
      - name: Checkout Private Action repo
        uses: actions/checkout@v2
        with:
          repository: YourOrg/Private-Action-Repo
          ref: v1.0.0
          token: ${{ secrets.GITHUB_ACCESS_TOKEN }} # github access token with previleges to checkout the private action repo
          path: .github/actions/Private-action
      
      # use local path reference for executing the action
      - name: Private Action X
        uses: ./.github/actions/Private-action
        
# PS: This is just a workaround as private actions are not (yet?) supported by Github!