Explicitly skip pkg install in tox test runs

Author: webknjaz

.github/workflows/ci-cd.yml

@@ -368,6 +368,7 @@ jobs:
         -p auto
         --parallel-live -vvvv
         --skip-missing-interpreters false
+        --skip-pkg-install
     - name: Send coverage data to Codecov
       uses: codecov/codecov-action@v1
       with: