Add support for running the build react map.

https://github.com/dcs-liberation/dcs_liberation/issues/2039

.github/workflows/build.yml

@@ -50,6 +50,11 @@ jobs:
           cd client
           npm ci
 
+      - name: Build client
+        run: |
+          cd client
+          npm run build
+
       - name: Build binaries
         run: |
           ./venv/scripts/activate