### Godot version

v4.0.beta11.official [91713ced8]

### System information

MX Linux 21

### Issue description

In Godot 3, TileMap had methods get_used_cells() and get_used_cells_by_id(). Godot 4's TileMap only has get_used_cells() and is missing get_used_cells_by_id().

get_used_cells_by_id() is highly useful in multiple cases, for example when trying to get all cells that are of road type, to randomly spawn a car.

Re-implementing get_used_cells_by_id() should be simple. The method could simply call get_used_cells(), and ignore all cells that are of the wrong ID.

### Steps to reproduce

N/A

### Minimal reproduction project

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