👷 introduce linter as CI

.github/workflows/lint.yml

@@ -0,0 +1,23 @@
+name: Lint with flake8
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Python 3.10
+      uses: actions/setup-python@v3
+      with:
+        python-version: 3.10
+    - name: Install dependencies
+      run: |
+        python -m pip install flake8
+    - name: Lint with flake8
+      run: |
+        make lint