Leaks on exiting game on exported builds + Fix

[SimranZenov]

Below are the errors I get in the godot log when exiting game, which is directly related to TileMapDual.
[Godot 4.6, Compatibility renderer, Windows, Nvidia RTX 3050]

ERROR: 1 RID allocations of type 'N5GLES36ShaderE' were leaked at exit.
ERROR: 15 RID allocations of type 'N5GLES37TextureE' were leaked at exit.
ERROR: 5 RID allocations of type 'N5GLES313CanvasTextureE' were leaked at exit.
ERROR: Texture with GL ID of 201: leaked 652456 bytes.
at: ~Utilities (drivers/gles3/storage/utilities.cpp:77)
ERROR: Texture with GL ID of 241: leaked 983024 bytes.
at: ~Utilities (drivers/gles3/storage/utilities.cpp:77)
ERROR: Texture with GL ID of 242: leaked 393208 bytes.
at: ~Utilities (drivers/gles3/storage/utilities.cpp:77)
ERROR: Texture with GL ID of 243: leaked 393208 bytes.
at: ~Utilities (drivers/gles3/storage/utilities.cpp:77)
ERROR: Texture with GL ID of 244: leaked 98296 bytes.
at: ~Utilities (drivers/gles3/storage/utilities.cpp:77)
+more

Verbose:
Leaked instance: TileData:503232602116
Leaked instance: TileData:503249379333
Leaked instance: TileData:503266156550
Leaked instance: TileData:503282933767
Leaked instance: TileData:503299710984
Leaked instance: TileData:503316488201
Leaked instance: TileData:503333265418
Leaked instance: TileData:503350042635
Leaked instance: TileData:503366819852
Leaked instance: TileData:503383597069
Leaked instance: TileData:503400374286
Leaked instance: TileData:503417151503
Leaked instance: TileData:503433928720
Leaked instance: TileData:503450705937
Leaked instance: TileData:503467483154
Leaked instance: TileData:503484260371
Leaked instance: TileData:503501037588
Leaked instance: TileData:503517814805
Leaked instance: TileData:503534592022
Leaked instance: TileData:503551369239
Leaked instance: TileData:503568146456
(x how ever many tiles you may have)

Here is the fix that worked for me. Added to tile_map_dual.gd:

func _exit_tree() -> void:
	# Break TileSetWatcher ↔ TileSet reference chain to prevent resource leaks at shutdown.
	# TileSetWatcher (RefCounted) connects to TileSet.changed signal and holds tile_set ref,
	# creating a cycle that prevents garbage collection after all Nodes are freed.
	if _tileset_watcher:
		_tileset_watcher.check_tile_set(null)

I'm not 100% sure if this is the most appropriate way to fix this issue, but maybe someone could look into it.