### Godot version

4.2

### System information

Godot v4.2.stable - Windows 10.0.19045 - Vulkan (Mobile) - dedicated AMD Radeon RX 6700 XT (Advanced Micro Devices, Inc.; 31.0.21001.45002) - AMD Ryzen 5 3600 6-Core Processor (12 Threads)

### Issue description

Tiles with light occluders still show shadows, when replacing them by code (set_cell) with a not occluding tile.
This does not happen when they are replaced with an empty cell (cell_id = -1) or erase_cell.

### Steps to reproduce

Make a new project with a Tilemap2D and a PointLight2D
Make 2 Tiles: One with an occluder and one without
Make the tiles placed by code.
Replace an occluding tile with a non occluding

### Minimal reproduction project

[TestForTilemap.zip](https://github.com/godotengine/godot/files/13539067/TestForTilemap.zip)

if (in_top_left_triangle) {
						ret += Vector2i(-1, 0);
					} else if (in_bottom_left_triangle) {
						ret += Vector2i(-1, 1);
					}
					break;
				case TileSet::TILE_LAYOUT_DIAMOND_RIGHT:
					ret = Vector2(ret.x / 2 - ret.y, ret.y + ret.x / 2).floor();
					if (in_top_left_triangle) {
						ret += Vector2i(0, -1);
					} else if (in_bottom_left_triangle) {
						ret += Vector2i(-1, 0);
					}
					break;
				case TileSet::TILE_LAYOUT_DIAMOND_DOWN:
					ret = Vector2(ret.x / 2 + ret.y, ret.y - ret.x / 2).floor();
					if (in_top_left_triangle) {
						ret += Vector2i(-1, 0);
					} else if (in_bottom_left_triangle) {
						ret += Vector2i(0, 1);
					}
					break;
			}
		}
	} else {
		ret = (ret + Vector2(0.00005, 0.00005)).floor();
	}
	return Vector2i(ret);
}
bool TileMap::is_existing_neighbor(TileSet::CellNeighbor p_cell_neighbor) const {