Update main.yml

Upgraded cache version to v4

Author: DanielArabadjiFC

.github/workflows/main.yml

@@ -23,7 +23,7 @@ jobs:
     - name: Check dependencies
       run: make doctor
 
-    - uses: actions/cache@v2
+    - uses: actions/cache@v4
       with:
         path: .venv
         key: ${{ runner.os }}-poetry-${{ hashFiles('poetry.lock') }}