I have next function in wordpress plugin 
```php
function wp_rest_blocks_init() {
	if ( ! function_exists( 'wp_use_widgets_block_editor' ) || ! wp_use_widgets_block_editor() ) {
		return;
	}

	register_rest_field(
		'widget',
		'has_blocks',
		[
			'get_callback'    => __NAMESPACE__ . '\\has_blocks_widget_get_callback',
			'update_callback' => null,
			'schema'          => [
				'description' => __( 'Has blocks.', 'wp-rest-blocks' ),
				'type'        => 'boolean',
				'context'     => [ 'embed', 'view', 'edit' ],
				'readonly'    => true,
			],
		]
	);

	register_rest_field(
		'widget',
		'blocks_data',
		[
			'get_callback'    => __NAMESPACE__ . '\\blocks_widget_get_callback',
			'update_callback' => null,
			'schema'          => [
				'description' => __( 'Blocks.', 'wp-rest-blocks' ),
				'type'        => 'object',
				'context'     => [ 'embed', 'view', 'edit' ],
				'readonly'    => true,
			],
		]
	);
}
```
in this function i want to change from
```php
	register_rest_field(
		'widget',
		'block_data',
		[
```
to
```php
	register_rest_field(
		'widget',
		'blocks_data',
		[
```
how can I change this in template functions.php and do not make changes in plugin?
