Clarify what `CharacterBody2D.floor_block_on_wall` actually does

**Your Godot version:**
4.4.1

**Issue description:**
On the CharacterBody2D page, it says for the `floor_block_on_wall` property description:

> If true, the body will be able to move on the floor only. This option avoids to be able to walk on walls, it will however allow to slide down along them.

However, this doesn't really tell me what the property does. The template script already has a player that will not walk on walls. Setting the property to false doesn't seem to make a difference.

Side note: "to be able to" should be "being able to".

**URL to the documentation page (if already existing):**
https://docs.godotengine.org/en/stable/classes/class_characterbody2d.html

https://docs.godotengine.org/en/stable/classes/class_characterbody3d.html