Avoid using require_dependency is Zeitwerk is enabled

[casperisfine]

Context

I'm trying to disable config.add_autoload_paths_to_load_path in our app, which cause require_dependency to straight up fail when called with an autoloaded path.

These were added in 1e55ee5 to workaround the classic autoloader limitations, but that's no longer a problem with Zeitwerk.

I'm not super happy with adding this kind of global config check in there, but I can't think of a better way.

@fxn, cc @eugeneius

cc @rafaelfranca @Edouard-chin @etiennebarrie

[rafaelfranca]

I'm merging but feel free to comment if you think there is a better way to do it.

[fxn]

👍

[fxn]

Cherry-picked to 6-0-stable.

[fxn]

I'd like to remove require_dependency from the code base, so I've rewritten this to use constant paths instead, see c7c3abe.

I have not forgotten the occurrence in helper, but need time to find a solution that I like. My desire would be to deprecate anything but module objects or blocks as arguments, but have to figure out helper :all, which cannot be deprecated, it has to be supported.