### 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)

if ((p_from_layout == TileSet::TILE_LAYOUT_STAIRS_RIGHT) ^ (p_offset_axis == TileSet::TILE_OFFSET_AXIS_VERTICAL)) {
				if (output.y < 0 && bool(output.y % 2)) {
					output = Vector2i(output.x + output.y / 2 - 1, output.y);
				} else {
					output = Vector2i(output.x + output.y / 2, output.y);
				}
			} else {
				if (output.x < 0 && bool(output.x % 2)) {
					output = Vector2i(output.x / 2 - 1, output.x + output.y * 2);
				} else {
					output = Vector2i(output.x / 2, output.x + output.y * 2);
				}
			}
			break;
		case TileSet::TILE_LAYOUT_DIAMOND_RIGHT:
		case TileSet::TILE_LAYOUT_DIAMOND_DOWN:
			if ((p_from_layout == TileSet::TILE_LAYOUT_DIAMOND_RIGHT) ^ (p_offset_axis == TileSet::TILE_OFFSET_AXIS_VERTICAL)) {
				if ((output.x + output.y) < 0 && (output.x - output.y) % 2) {
					output = Vector2i((output.x + output.y) / 2 - 1, output.y - output.x);
				} else {
					output = Vector2i((output.x + output.y) / 2, -output.x + output.y);
				}
			} else {
				if ((output.x - output.y) < 0 && (output.x + output.y) % 2) {
					output = Vector2i((output.x - output.y) / 2 - 1, output.x + output.y);
				} else {
					output = Vector2i((output.x - output.y) / 2, output.x + output.y);
				}
			}
			break;