Fix copy-pasta function name 😒

includes/wp-cli/class-data.php

@@ -13,7 +13,7 @@ class Data extends \WP_CLI_Command {
 	 *
 	 * @subcommand flush-cache
 	 */
-	public function purge( $args, $assoc_args ) {
+	public function flush_internal_cache( $args, $assoc_args ) {
 		$flushed = wp_cache_delete( \Automattic\WP\Cron_Control\Cron_Options_CPT::CACHE_KEY );
 
 		if ( $flushed ) {