name: Ubuntu Qt CI

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

jobs:
  build:

    strategy:
      fail-fast: false
      matrix:
        name: [ubuntu-18.04, ubuntu-20.04]
        include:
          - name: ubuntu-18.04
            os: ubuntu-18.04
            artifact: minutor
          - name: ubuntu-20.04
            os: ubuntu-20.04
            artifact: minutor
    runs-on: ${{ matrix.os }}

    steps:
    - uses: actions/checkout@v2

    - name: Install Qt
      run: sudo apt-get install qt5-default -y

    - name: Create BUILD folder
      run: |
        mkdir ../build
    
    - name: Build (Ubuntu)
      working-directory: ../build
      run: |
        qmake ${{ github.workspace }}/${{ matrix.artifact }}.pro
        make
      env:
        # only needed for Ubuntu-16.04
        LD_LIBRARY_PATH: '${{ runner.workspace }}/Qt/5.5/gcc_64/lib'
   
    - name: Archive build result
      uses: actions/upload-artifact@v2
      with:
        name: Binary ${{ matrix.name }}
        path: ${{ runner.workspace }}/build/${{ matrix.artifact }}

Create own workflow for Ubuntu
Create own workflow for Ubuntu