Updated GitHub Action to use pipenv

Author: rofrano

.github/workflows/ci.yml

@@ -44,9 +44,8 @@ jobs:
 
       - name: Install dependencies
         run: |
-          python -m pip install -U pip poetry
-          poetry config virtualenvs.create false
-          poetry install
+          python -m pip install -U pip pipenv
+          pipenv install --system --dev
 
       - name: Linting
         run: |