Update codecov to v2

Author: WisdomPill

.github/workflows/ci.yml

@@ -94,7 +94,7 @@ jobs:
           REDIS: ${{ matrix.redis-version }}
 
       - name: Upload coverage
-        uses: codecov/codecov-action@v1
+        uses: codecov/codecov-action@v2
         with:
           env_vars: DJANGO,REDIS,PYTHON
           flags: tests