Revert setting path when ResourceFormatLoader::CACHE_MODE_IGNORE

[adamscott]

As discussed with @reduz in the Godot contributors chat.

The current behaviour could be linked to a multitude of reloading issues. To cite Juan:

If cache mode is IGNORE, it should never set the path, because there can only be a single resource using a single path, and cache mode IGNORE is used in all sort of situations when you want to load a version of the resource without setting the path

[Maran23]

Looks like @reduz did the same some minutes before you. 😄
#71170

[adamscott]

Duplicate of #71170. (:laughing:)