Link to the submitting documentation when submitting an asset

[aaronfranke]

https://docs.godotengine.org/en/latest/tutorials/assetlib/uploading_to_assetlib.html

I recently wrote the "Submission guidelines" section, but the asset library currently does not link to this page. I think it should, so that users can read the guidelines and other submission information.

[bojidar-bg]

Should the link be to en/lastest or to en/stable?

[aaronfranke]

Either is fine to me. I usually use latest for documentation that isn't the class reference or game creation tutorials, since latest might be more updated, and for these kinds of articles, they shouldn't contain any information that depends on the Godot version being used.