update flake8 setup

.github/workflows/main.yaml

@@ -7,11 +7,19 @@ on:
     branches: ["main"]
 
 jobs:
-  
   test:
     steps:
       - name: Checkout repository
         uses: actions/checkout@v5.0.0
 
       - name: Run tests
-        run: python3 test_main.py
+        run: |
+          python3 test_main.py
+
+      - name: setup pyflake8
+        run: |
+          apt update
+          apt install flake8 -y
+
+      - name: run flake8
+        run: flake8 .