Revert "Use python 3.9 venv for cronjob"

This reverts commit 08d0c71.

Author: SimmonsRitchie

.github/workflows/cron.yml

@@ -25,18 +25,27 @@ jobs:
     steps:
       - uses: actions/checkout@v1
 
-      - name: Set up Python 3.9
+      - name: Set up Python 3.7
         uses: actions/setup-python@v1
         with:
-          python-version: 3.9
+          python-version: 3.7
 
       - name: Install Pipenv
         uses: dschep/install-pipenv-action@v1
 
+      - name: Cache Python dependencies
+        uses: actions/cache@v1
+        with:
+          path: .venv
+          key: pip-3.7-${{ hashFiles('**/Pipfile.lock') }}
+          restore-keys: |
+            pip-3.7-
+            pip-
+
       - name: Install dependencies
         run: pipenv sync
         env:
-          PIPENV_DEFAULT_PYTHON_VERSION: 3.9
+          PIPENV_DEFAULT_PYTHON_VERSION: 3.7
 
       - name: Run scrapers
         run: |