add flake8 linting workflow for Python code

Author: summerduck

.github/workflows/lint.yml

@@ -0,0 +1,21 @@
+
+name: flake8 Lint
+
+on: [push]
+
+jobs:
+  flake8-lint:
+    runs-on: ubuntu-latest
+    name: Lint
+    steps:
+      - name: Check out source repository
+        uses: actions/checkout@v4
+      - name: Set up Python environment
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.10"
+      - name: flake8 Lint
+        uses: py-actions/flake8@v2
+        with:
+          ignore: "F401,W503"
+          max-line-length: "120"