### Godot version

v4.0.3.stable.mono.official [5222a99f5]

### System information

macOS Monterey 12.6.6 (21G646)

### Issue description

When creating a tileset by code with custom data layers, removing a layer with `remove_custom_data_layer` does not update the name-to-layer mapping; `get_custom_data_layer_by_name` will continue to return that layer's original index.

This has a downstream effect of causing TileData objects attempting to use `get_custom_data('Layer B')` to return invalid data (whatever custom data is now in Layer B's old index; e.g. Layer C).

I would expect that after using `remove_custom_data_layer`, I would be able to still use `get_custom_data_layer_by_name` on that tileset.

### Steps to reproduce

Run this code to see that getting Layer B by name after removing the first layer continues to return its original index (1) when in reality it is now at index 0.
```
	var tileset:TileSet = TileSet.new()

	tileset.add_custom_data_layer()
	tileset.set_custom_data_layer_name(0, 'Layer A')
	tileset.set_custom_data_layer_type(0, TYPE_INT)

	tileset.add_custom_data_layer()
	tileset.set_custom_data_layer_name(1, 'Layer B')
	tileset.set_custom_data_layer_type(1, TYPE_STRING)

	print('Layer index 0 name : ', tileset.get_custom_data_layer_name(0)) # Layer A
	print('Layer index 1 name : ', tileset.get_custom_data_layer_name(1)) # Layer B
	print('Layer B is on index : ', tileset.get_custom_data_layer_by_name("Layer B")) # 1

	print('----- removing custom data layer 0 -----')
	tileset.remove_custom_data_layer(0)

	print('Layer index 0 name : ', tileset.get_custom_data_layer_name(0)) # Layer B
	print('Layer index 1 name : ', tileset.get_custom_data_layer_name(1)) # prints an error, as expected
	print('Layer B is on index : ', tileset.get_custom_data_layer_by_name("Layer B")) # returns 1 still! should return 0.
```

### Minimal reproduction project

[RemoveCustomDataLayer.zip](https://github.com/godotengine/godot/files/11804762/RemoveCustomDataLayer.zip)

ERR_FAIL_COND_V(p_atlas_coords != Vector2i(), false);
	return scenes.has(p_alternative_tile);
}
int TileSetScenesCollectionSource::create_scene_tile(Ref<PackedScene> p_packed_scene, int p_id_override) {
	ERR_FAIL_COND_V_MSG(p_id_override >= 0 && scenes.has(p_id_override), INVALID_TILE_ALTERNATIVE, vformat("Cannot create scene tile. Another scene tile exists with id %d.", p_id_override));
	int new_scene_id = p_id_override >= 0 ? p_id_override : next_scene_id;
	scenes[new_scene_id] = SceneData();
	scenes_ids.push_back(new_scene_id);
	scenes_ids.sort();
	set_scene_tile_scene(new_scene_id, p_packed_scene);
	_compute_next_alternative_id();
	emit_signal(SNAME("changed"));
	return new_scene_id;
}
void TileSetScenesCollectionSource::set_scene_tile_id(int p_id, int p_new_id) {
	ERR_FAIL_COND(p_new_id < 0);
	ERR_FAIL_COND(!has_scene_tile_id(p_id));
	ERR_FAIL_COND(has_scene_tile_id(p_new_id));
	scenes[p_new_id] = SceneData();
	scenes[p_new_id] = scenes[p_id];
	scenes_ids.push_back(p_new_id);
	scenes_ids.sort();
	_compute_next_alternative_id();
	scenes.erase(p_id);
	scenes_ids.erase(p_id);
	emit_signal(SNAME("changed"));
}
void TileSetScenesCollectionSource::set_scene_tile_scene(int p_id, Ref<PackedScene> p_packed_scene) {