### 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)

#endif 
	_clear_runtime_update_tile_data();
	
	for (int i = 0; i < DIRTY_FLAGS_MAX; i++) {
		dirty.flags[i] = false;
	}
	
	Vector<Vector2i> to_delete;
	for (SelfList<CellData> *cell_data_list_element = dirty.cell_list.first(); cell_data_list_element; cell_data_list_element = cell_data_list_element->next()) {
		CellData &cell_data = *cell_data_list_element->self();
		
		if (cell_data.cell.source_id == TileSet::INVALID_SOURCE) {
			to_delete.push_back(cell_data.coords);
		}
	}
	
	for (const Vector2i &coords : to_delete) {
		tile_map.erase(coords);
	}
	
	dirty.cell_list.clear();
}
void TileMapLayer::set_cell(const Vector2i &p_coords, int p_source_id, const Vector2i p_atlas_coords, int p_alternative_tile) {
	
	Vector2i pk(p_coords);
	HashMap<Vector2i, CellData>::Iterator E = tile_map.find(pk);
	int source_id = p_source_id;
	Vector2i atlas_coords = p_atlas_coords;
	int alternative_tile = p_alternative_tile;
	if ((source_id == TileSet::INVALID_SOURCE || atlas_coords == TileSetSource::INVALID_ATLAS_COORDS || alternative_tile == TileSetSource::INVALID_TILE_ALTERNATIVE) &&