### 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
ERR_FAIL_COND(!tile_set.is_valid());
	if (!Engine::get_singleton()->is_editor_hint()) {
		return;
	}
	
	RenderingServer *rs = RenderingServer::get_singleton();
	Vector2 quadrant_pos = map_to_local(p_quadrant->coords * get_effective_quadrant_size(p_quadrant->layer));
	for (const Vector2i &E_cell : p_quadrant->cells) {
		const TileMapCell &c = get_cell(p_quadrant->layer, E_cell, true);
		TileSetSource *source;
		if (tile_set->has_source(c.source_id)) {
			source = *tile_set->get_source(c.source_id);
			if (!source->has_tile(c.get_atlas_coords()) || !source->has_alternative_tile(c.get_atlas_coords(), c.alternative_tile)) {
				continue;
			}
			TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
			if (atlas_source) {
				Vector2i grid_size = atlas_source->get_atlas_grid_size();
				if (!atlas_source->get_runtime_texture().is_valid() || c.get_atlas_coords().x >= grid_size.x || c.get_atlas_coords().y >= grid_size.y) {