chore: fixes a build failure with node:16-alpine as builder

https://github.com/iris-connect/iris-client/actions/runs/2460108944

iris-client-fe/Dockerfile

@@ -1,28 +1,25 @@
-FROM node:16-alpine as builder
+FROM caddy:2.5.1-builder-alpine as builder
 
 # make the 'app' folder the current working directory
 WORKDIR /app
 
 # copy both 'package.json' and 'package-lock.json' (if available)
 COPY package*.json ./
 
-# install project dependencies
-RUN npm ci
-
 # copy project files and folders to the current working directory (i.e. 'app' folder)
 COPY . .
 
 ARG VUE_APP_VERSION_ID=production
 ARG VUE_APP_BUILD_ID=local
 
 # build app for production with minification
-RUN npm run build
+RUN xcaddy build
 
 FROM caddy:2.5.1-alpine
 
 # copy build artifacts to webserver root
 RUN rm -rf /usr/share/caddy
-COPY --from=builder /app/dist /usr/share/caddy
+COPY --from=builder /app/caddy /usr/share/caddy
 
 # copy webserver configuration
 COPY ./Caddyfile /etc/caddy/Caddyfile