### 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)

if (p_to_pos >= 0 && p_to_pos <= terrain_set) {
		terrain_set += 1;
	}
}
void TileData::move_terrain_set(int p_from_index, int p_to_pos) {
	if (p_from_index == terrain_set) {
		terrain_set = (p_from_index < p_to_pos) ? p_to_pos - 1 : p_to_pos;
	} else {
		if (p_from_index < terrain_set) {
			terrain_set -= 1;
		}
		if (p_to_pos <= terrain_set) {
			terrain_set += 1;
		}
	}
}
void TileData::remove_terrain_set(int p_index) {
	if (p_index == terrain_set) {
		terrain_set = -1;
		for (int i = 0; i < 16; i++) {
			terrain_peering_bits[i] = -1;
		}
	} else if (terrain_set > p_index) {
		terrain_set -= 1;
	}
}
void TileData::add_terrain(int p_terrain_set, int p_to_pos) {