### 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_peering_bit == TileSet::CELL_NEIGHBOR_MAX, -1);
	ERR_FAIL_COND_V(!is_valid_bit[p_peering_bit], -1);
	return bits[p_peering_bit];
}
void TileSet::TerrainsPattern::from_array(Array p_terrains) {
	set_terrain(p_terrains[0]);
	int in_array_index = 1;
	for (int i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
		if (is_valid_bit[i]) {
			ERR_FAIL_INDEX(in_array_index, p_terrains.size());
			set_terrain_peering_bit(TileSet::CellNeighbor(i), p_terrains[in_array_index]);
			in_array_index++;
		}
	}
}
Array TileSet::TerrainsPattern::as_array() const {
	Array output;
	output.push_back(get_terrain());
	for (int i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
		if (is_valid_bit[i]) {
			output.push_back(bits[i]);
		}
	}
	return output;
}
TileSet::TerrainsPattern::TerrainsPattern(const TileSet *p_tile_set, int p_terrain_set) {