chore(with-docker): don't copy package.json twice (#39896)

the directory `/app/.next/standalone` already contains a copy of the package.json so we can skip copying it before we copy the standalone dir

## Documentation / Examples

- [x] Make sure the linting passes by running `pnpm lint`
- [x] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)

Co-authored-by: JJ Kasper <jj@jjsweb.site>

examples/with-docker-compose/next-app/prod.Dockerfile

@@ -42,8 +42,6 @@ RUN adduser --system --uid 1001 nextjs
 USER nextjs
 
 COPY --from=builder /app/public ./public
-COPY --from=builder /app/next.config.js .
-COPY --from=builder /app/package.json .
 
 # Automatically leverage output traces to reduce image size
 # https://nextjs.org/docs/advanced-features/output-file-tracing

examples/with-docker-multi-env/docker/development/Dockerfile

@@ -32,10 +32,7 @@ ENV NODE_ENV=production
 RUN addgroup -g 1001 -S nodejs
 RUN adduser -S nextjs -u 1001
 
-# You only need to copy next.config.js if you are NOT using the default configuration
-# COPY --from=builder /app/next.config.js ./
 COPY --from=builder /app/public ./public
-COPY --from=builder /app/package.json ./package.json
 
 # Automatically leverage output traces to reduce image size
 # https://nextjs.org/docs/advanced-features/output-file-tracing

examples/with-docker-multi-env/docker/production/Dockerfile

@@ -33,10 +33,7 @@ ENV NODE_ENV=production
 RUN addgroup -g 1001 -S nodejs
 RUN adduser -S nextjs -u 1001
 
-# You only need to copy next.config.js if you are NOT using the default configuration
-# COPY --from=builder /app/next.config.js ./
 COPY --from=builder /app/public ./public
-COPY --from=builder /app/package.json ./package.json
 
 # Automatically leverage output traces to reduce image size
 # https://nextjs.org/docs/advanced-features/output-file-tracing

examples/with-docker-multi-env/docker/staging/Dockerfile

@@ -33,10 +33,7 @@ ENV NODE_ENV=production
 RUN addgroup -g 1001 -S nodejs
 RUN adduser -S nextjs -u 1001
 
-# You only need to copy next.config.js if you are NOT using the default configuration
-# COPY --from=builder /app/next.config.js ./
 COPY --from=builder /app/public ./public
-COPY --from=builder /app/package.json ./package.json
 
 # Automatically leverage output traces to reduce image size
 # https://nextjs.org/docs/advanced-features/output-file-tracing

examples/with-docker/Dockerfile

@@ -41,10 +41,7 @@ ENV NODE_ENV production
 RUN addgroup --system --gid 1001 nodejs
 RUN adduser --system --uid 1001 nextjs
 
-# You only need to copy next.config.js if you are NOT using the default configuration
-# COPY --from=builder /app/next.config.js ./
 COPY --from=builder /app/public ./public
-COPY --from=builder /app/package.json ./package.json
 
 # Automatically leverage output traces to reduce image size
 # https://nextjs.org/docs/advanced-features/output-file-tracing