Fix CharacterBody2D get_slide_collision docs

The indentation was off and the code usage was incorrect for Godot 4.0 GDScript.

(cherry picked from commit 2b6e1550ffbbe8a5f0696f2ffbc657ed36e8faf2)

doc/classes/CharacterBody2D.xml

@@ -67,8 +67,8 @@
 				[codeblocks]
 				[gdscript]
 				for i in get_slide_collision_count():
-				var collision = get_slide_collision(i)
-				print("Collided with: ", collision.collider.name)
+				    var collision = get_slide_collision(i)
+				    print("Collided with: ", collision.get_collider().name)
 				[/gdscript]
 				[csharp]
 				for (int i = 0; i < GetSlideCollisionCount(); i++)