Update Dockerfile

Dockerfile

@@ -1,5 +1,8 @@
 FROM node:16-alpine as build-frontend
 
+RUN --mount=type=secret,id=PUBLIC_BACKEND_WS_URL,mode=0444,required=true \
+ export PUBLIC_BACKEND_WS_URL=$(cat /run/secrets/PUBLIC_BACKEND_WS_URL)
+ 
 # Set the working directory
 WORKDIR /app
 
@@ -10,6 +13,7 @@ RUN npm ci --prefix frontend/
 
 # Copy the rest of the application files
 COPY frontend/ /app/frontend/
+
 RUN npm run build --prefix frontend/
 
 # Start a new stage using python:3.9-alpine