add more args in docker file

Dockerfile

@@ -1,7 +1,7 @@
 # build stage
 FROM node:lts-alpine as build-stage
 ARG CONTAINER_APP_ROOT="/app"
-
+ARG FRONTEND_PORT=8080
 RUN npm update npm -g
 RUN npm config set "@fortawesome:registry" https://npm.fontawesome.com/
 RUN npm config set "//npm.fontawesome.com/:_authToken" 58624E90-2685-43C6-BF0F-0BFECCE11CD2
@@ -23,5 +23,5 @@ RUN npm run build
 FROM nginx:1.25.2 as production-stage
 COPY --from=build-stage /app/dist /usr/share/nginx/html
 COPY frontend/nginx_docker.conf /etc/nginx/conf.d/default.conf
-EXPOSE 8080
+EXPOSE ${FRONTEND_PORT}
 CMD ["nginx", "-g", "daemon off;"]