🎨 lint code base with ruff

Author: enryH

.github/workflows/cdci.yml

@@ -27,9 +27,13 @@ jobs:
           python-version: ${{ matrix.python-version }}
           cache: "pip" # caching pip dependencies
           cache-dependency-path: "**/pyproject.toml"
-      - name: Install dependencies
+      - name: lint package code with ruff 
         run: |
           python -m pip install --upgrade pip
+          pip install ruff
+          ruff check src
+      - name: Install dependencies for testing
+        run: |
           pip install pytest
           pip install -e .
       - name: Run tests