Allow output_path to be remote url

[oscargala]

We have a case where our css and js files are on a cdn and we have encore build all the files remotely on the cdn after we do a push. the entrypoints.json is therefore also remotely on the cdn server.

I can add this in the config:

webpack_encore:
output_path: "https://cdn.blabla.com/experimental"

But then the file_exists check in src/Asset/EntryPointLookup.php on line 120 halts the process.
Whereas the file_get_contents on line 127 would work perfectly well with the remote url.

So could there be a way to bypass the file_exists check if the output_path is a url? Or add a config option "remote" or something like that?