build(actions): add pylint workflow

add pylint workflow for pushes and PRs on all branches

.github/workflows/pylint.yml

@@ -0,0 +1,31 @@
+name: Pylint
+
+on:
+  push:
+    branches:
+    - "7.9"
+    - "8.0"
+    - jython
+    - main
+  pull_request:
+    branches:
+    - main
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python 3.9
+      uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install pylint
+    - name: Analysing the code with pylint
+      run: |
+        pylint src