code quality checks with wily

.github/workflows/code_quality.yml

@@ -0,0 +1,31 @@
+name: Code quality checks
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  wily:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+
+      - name: fetch refs and tags
+        run: git fetch --all
+
+      - name: Set up Python 3.8
+        uses: actions/setup-python@v1
+        with:
+          python-version: "3.8"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install wily
+
+      - name: Check code quality changes with wily
+        run: |
+          wily build src/
+          wily diff src/ -r origin/master