build: test Python 3 using GitHub Actions-based CI

.github/workflows/pythonpackage.yml

@@ -0,0 +1,33 @@
+name: Python 3 testing
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      max-parallel: 1
+      matrix:
+        python-version: [3.8]  # [2.7, 3.5, 3.6, 3.7]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v1
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Compile Node.js
+      run: |
+        python ./configure.py
+        make -j2 V=1
+    - name: Test JS Suites
+      run: |
+        python tools/test.py -j 2 -p dots --report --mode=release --flaky-tests=dontcare default
+    - name: Test C++ Suites
+      run: |
+        make -j1 V=1 test/addons/.buildstamp test/js-native-api/.buildstamp test/node-api/.buildstamp
+        python tools/test.py -j 2 -p dots --report --mode=release --flaky-tests=dontcare addons js-native-api node-api
+    - name: Make lint
+      run: |
+        make lint-py-build || true
+        NODE=$(which node) make lint lint-py