Fixing messages generation in Front container

front/Dockerfile

@@ -1,13 +1,13 @@
-FROM thecodingmachine/workadventure-back-base:latest as builder
-COPY --chown=docker:docker messages .
-WORKDIR /var/www/messages
+FROM node:14.15.4-buster-slim@sha256:cbae886186467bbfd274b82a234a1cdfbbd31201c2a6ee63a6893eefcf3c6e76 as builder
+WORKDIR /usr/src
+COPY messages .
 RUN yarn install && yarn proto
 
 # we are rebuilding on each deploy to cope with the PUSHER_URL environment URL
 FROM thecodingmachine/nodejs:14-apache
 
 COPY --chown=docker:docker front .
-COPY --from=builder --chown=docker:docker /var/www/messages/generated /var/www/html/src/Messages/generated
+COPY --from=builder --chown=docker:docker /usr/src/generated /var/www/html/src/Messages/generated
 
 # Removing the iframe.html file from the final image as this adds a XSS attack.
 # iframe.html is only in dev mode to circumvent a limitation