Fix incorrect class_name declaration in 2D physics tests demo (#1188)

xr/openxr_hand_tracking_demo/pickup/pickup_able_body.gd

@@ -1,6 +1,5 @@
-extends RigidBody3D
 class_name PickupAbleBody3D
-
+extends RigidBody3D
 
 var highlight_material : Material = preload("res://shaders/highlight_material.tres")
 var picked_up_by : Area3D
@@ -9,6 +8,7 @@ var closest_areas : Array
 var original_parent : Node3D
 var tween : Tween
 
+
 # Called when this object becomes the closest body in an area
 func add_is_closest(area : Area3D) -> void:
 	if not closest_areas.has(area):

xr/openxr_hand_tracking_demo/pickup/pickup_handler.gd

@@ -1,6 +1,6 @@
 @tool
-extends Area3D
 class_name PickupHandler3D
+extends Area3D
 
 # This area3D class detects all physics bodys based on
 # PickupAbleBody3D within range and handles the logic
@@ -24,6 +24,7 @@ var closest_body : PickupAbleBody3D
 var picked_up_body: PickupAbleBody3D
 var was_pickup_pressed : bool = false
 
+
 # Update our detection range.
 func _update_detect_range() -> void:
 	var shape : SphereShape3D = $CollisionShape3D.shape