fix: permissions in with-docker example

[Kinbaum]

What

This pr addresses an issue in Docker where the cache and the creation of its contents throw the following error:

[Error: EACCES: permission denied, mkdir '/app/.next/cache'] {
errno: -13,
code: 'EACCES',
syscall: 'mkdir',
path: '/app/.next/cache'

[samcx]

Thank you for submitting a !

[ijjk]

Allow CI Workflow Run

• approve CI run for commit: effe396

Note: this should only be enabled once the PR is ready to go and can only be enabled by a maintainer

[dodyagung]

dont need to pass -p (only single folder)
and also I think dont need to write this mkdir command (and RUN mkdir -p .next/cache below) because "COPY --from=builder --chown=nextjs:nodejs" automatically create the folder for you

[Kinbaum]

A few things on this

• .next/cache doesn't exist in the builder phase and only shows up when the app starts.
• Without explicitly making the directory in the Dockerfile, you get the error I've identified.
• If you don't modify the permissions of the cache folder (changing owner/user is not enough), then you'll get the same error on the creation of .next/cache/images

If your not seeing any of these issue, then I would asked what version of next are you using, and are you statically generating any pages?

Navigating to a statically generated page throws the errors in the logs.

@dodyagung @samcx