add nightly screenshot/puppeteer Github action stub

.github/workflows/nightly.yml

@@ -0,0 +1,17 @@
+name: Nightly Test Pipeline
+
+on:
+  schedule:
+    # Runs every day at 12:00 AM UTC
+    - cron: '0 0 * * *'
+
+jobs:
+  nightly:
+    runs-on: ubuntu-latest
+    container:
+      image: scalableminds/puppeteer:fix_wk_nightly
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+