use better copy on backend/Dockerfile

backend/Dockerfile

@@ -1,3 +1,5 @@
+# syntax=docker/dockerfile:1.7-labs
+
 # Stage 1: Build the application
 FROM node:20 AS build
 
@@ -13,9 +15,11 @@ FROM ghcr.io/ticketz-oss/node
 WORKDIR /usr/src/app
 
 # Copy only the necessary build artifacts from the build stage
-COPY --from=build /usr/src/app/dist ./dist
-COPY --from=build /usr/src/app/node_modules ./node_modules
-COPY --from=build /usr/src/app/package.json ./package.json
+COPY --from=build --parents \
+  /usr/src/app/./dist \
+  /usr/src/app/./node_modules \
+  /usr/src/app/./package.json \
+  .
 
 ENV NODE_ENV=production
 ENV PORT=3000