Update notebook-pr.yaml

Author: iamzoltan

.github/workflows/notebook-pr.yaml

@@ -64,6 +64,7 @@ jobs:
       - name: Install dependencies
         if: "!contains(env.COMMIT_MESSAGE, 'skip ci')"
         run: |
+          sudo apt-get update
           sudo apt-get install python3-opencv -y
           python -m pip install --upgrade pip wheel
           pip install -r requirements.txt