### Tested versions

- First reproducible in: v4.2.dev5.official [e3e2528ba]
- Reproducible in: v4.2.stable.official [46dc27791], v4.2.dev5.official [e3e2528ba], v4.2.dev6.official [57a6813bb]
- Not reproducible in: v4.1.3.stable.official [f06b6836a], v4.2.dev1.official [0c2144da9], v4.2.dev2.official [da81ca62a], v4.2.dev3.official [013e8e3af], v4.2.dev4.official [549fcce5f]

### System information

Godot v4.2.stable - Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1080 (NVIDIA; 31.0.15.4617) - Intel(R) Core(TM) i5-8600K CPU @ 3.60GHz (6 Threads)

### Issue description

The `TileSet` `set_occlusion_layer_light_mask` method does not properly update the `TileSet`'s light mask, causing shadows to still be cast by the `TileSet` even when the light mask is changed using the method to a mask different from a given light source (or even an empty light mask). In v4.1.3.stable.official [f06b6836a] this method was working properly.

### Steps to reproduce

- Download and open the `MRPSetOcclusionLayerTileSet_4.2-stable` project folder using one of the reproducible Godot versions noted above.
- Run the project, and press the spacebar key. This will toggle the occlusion layer light mask value of the on-screen `TileMap`'s `TileSet` occlusion light mask between 0 and 1. You will see that the `TileMap` still casts shadows regardless of the new value of its `TileSets`'s occlusion layer light mask.

### Minimal reproduction project (MRP)

[MRPSetOcclusionLayerTileSetBug.zip](https://github.com/godotengine/godot/files/13592741/MRPSetOcclusionLayerTileSetBug.zip)

DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE, 0, 1);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE, 5, 0);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_RIGHT_SIDE, 4, 5);
			} else {
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE, 3, 4);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_BOTTOM_SIDE, 4, 5);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE, 5, 0);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE, 0, 1);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_TOP_SIDE, 1, 2);
				DRAW_SIDE_IF_NEEDED(TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE, 2, 3);
			}
		}
	}
#undef DRAW_SIDE_IF_NEEDED
}
Ref<Resource> TileMap::get_transformed_polygon(Ref<Resource> p_polygon, int p_alternative_id) {
	if (!bool(p_alternative_id & (TileSetAtlasSource::TRANSFORM_FLIP_H | TileSetAtlasSource::TRANSFORM_FLIP_V | TileSetAtlasSource::TRANSFORM_TRANSPOSE))) {
		return p_polygon;
	}
	{
		HashMap<Pair<Ref<Resource>, int>, Ref<Resource>, PairHash<Ref<Resource>, int>>::Iterator E = polygon_cache.find(Pair<Ref<Resource>, int>(p_polygon, p_alternative_id));
		if (E) {
			return E->value;
		}
	}
	Ref<ConvexPolygonShape2D> col = p_polygon;
	if (col.is_valid()) {
		Ref<ConvexPolygonShape2D> ret;
		ret.instantiate();
		ret->set_points(_get_transformed_vertices(col->get_points(), p_alternative_id));