added flask installation dependency

.github/workflows/dev_cloudrun.yml

@@ -66,11 +66,12 @@ jobs:
       - name: Checkout the code
         uses: actions/checkout@v2
 
-      - name: Install Python 3.11
+      - name: Install Python and dependencies
         run: |
           sudo apt update
           sudo apt install python3.11
           python3.11 --version
+          pip3 install Flask
 
       - name: Run unit test
         run: python3 -m unittest discover -s tests