### 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)

int16_t x = decode_uint16(&local[0]);
		int16_t y = decode_uint16(&local[2]);
		if (p_format == TileMapLayer::FORMAT_3) {
			uint16_t source_id = decode_uint16(&local[4]);
			uint16_t atlas_coords_x = decode_uint16(&local[6]);
			uint16_t atlas_coords_y = decode_uint16(&local[8]);
			uint16_t alternative_tile = decode_uint16(&local[10]);
			set_cell(Vector2i(x, y), source_id, Vector2i(atlas_coords_x, atlas_coords_y), alternative_tile);
		} else {
#ifndef DISABLE_DEPRECATED
			
			uint32_t v = decode_uint32(&local[4]);
			
			bool flip_h = v & (1UL << 29);
			bool flip_v = v & (1UL << 30);
			bool transpose = v & (1UL << 31);
			v &= (1UL << 29) - 1;
			
			int16_t coord_x = 0;
			int16_t coord_y = 0;
			if (p_format == TileMapLayer::FORMAT_2) {
				coord_x = decode_uint16(&local[8]);
				coord_y = decode_uint16(&local[10]);
			}
			const Ref<TileSet> &tile_set = tile_map_node->get_tileset();
			if (tile_set.is_valid()) {
				Array a = tile_set->compatibility_tilemap_map(v, Vector2i(coord_x, coord_y), flip_h, flip_v, transpose);
				if (a.size() == 3) {
					set_cell(Vector2i(x, y), a[0], a[1], a[2]);
				} else {