get_property_list method documentation unclear on what properties are returned

[jacob-winkler]

Your Godot version:
4.3

Issue description:
The documentation isn't clear that this only returns properties that have been exported. Reading the documentation I was expecting this method to return all of the properties on my class, regardless of whether they were exported or not. A Godot property is different from a C# property (not sure if "property" is a concept in gdscript that could also cause confusion). Would be great if this was clarified in the docs.
URL to the documentation page (if already existing):
https://docs.godotengine.org/en/stable/classes/class_object.html#id2

[mateuseap]

I've made explicit in my PR that the get_method_list method returns a list containing only the exported properties.