Fixed dockerfile

Dockerfile

@@ -9,7 +9,9 @@ COPY server/ ./server/
 RUN cd server && npm install && npm run build
 
 FROM node:latest AS serve
-WORKDIR /root/
+WORKDIR /usr/src/app
+COPY package*.json ./
+RUN npm install --only=production
 COPY --from=server-build /usr/src/app/server/dist ./distServer
 COPY --from=client-build /usr/src/app/client/dist ./distClient
 CMD ["node", "./distServer/app.js"]