Dymanic-ish GitHub Actions Workflow

checkout.yaml

jobs:

  setup:
    name: Setup Workflow Variables
    runs-on: ubuntu-latest
    outputs:
      matrix: ${{ steps.matrix.outputs.matrix }}

    steps:
    - name: Generate Build matrix
      id: matrix
      shell: pwsh
      run: |
        $matrix = @{include = @()}
        # Possible loop
        $item = @{
            Repo = "blah"
            PAT = "${{ secrets.PAT }}"
        }

        $matrix['include'] += $item
        # End Loop

        Write-Host ("::set-output name=matrix::{0}" -f ($matrix | ConvertTo-Json -Compress))

  checkout:
    name: Build Stack Overflow image (${{ matrix.Repo }}
    runs-on: ubuntu-latest
    needs: [setup]
    strategy:
      fail-fast: false
      matrix: ${{ fromJSON(needs.setup.outputs.matrix) }}

    steps:

    - name: Checkout repo
      uses: actions/checkout@v2
      with:
        repository: ${{ matrix.Repo }}
        token: ${{ matrix.PAT }}
        path: './somepath/${{ matrix.Repo }}'