### 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)

return true;
			} else if (components[1] == "coords_level") {
				for (int i = 0; i < a.size(); i += 2) {
					Array key = a[i];
					Array value = a[i + 1];
					set_coords_level_tile_proxy(key[0], key[1], value[0], value[1]);
				}
				return true;
			} else if (components[1] == "alternative_level") {
				for (int i = 0; i < a.size(); i += 2) {
					Array key = a[i];
					Array value = a[i + 1];
					set_alternative_level_tile_proxy(key[0], key[1], key[2], value[0], value[1], value[2]);
				}
				return true;
			}
			return false;
		} else if (components.size() == 1 && components[0].begins_with("pattern_") && components[0].trim_prefix("pattern_").is_valid_int()) {
			int pattern_index = components[0].trim_prefix("pattern_").to_int();
			for (int i = patterns.size(); i <= pattern_index; i++) {
				add_pattern(p_value);
			}
			return true;
		}
#ifndef DISABLE_DEPRECATED
	}
#endif 
	return false;
}
bool TileSet::_get(const StringName &p_name, Variant &r_ret) const {