Traverse downward from WP_CLI_ROOT, which isn't this dir

Author: danielbachhuber

src/Server_Command.php

@@ -78,8 +78,8 @@ function __invoke( $_, $assoc_args ) {
 		// Get the path to the router file
 		$router_path = WP_CLI_ROOT . '/vendor/wp-cli/server-command/router.php';
 		if ( ! file_exists( $router_path ) ) {
-			// server-command must've been built as the base Phar
-			$router_path = WP_CLI_ROOT . '/router.php';
+			// server command must've been built with vendor/wp-cli/wp-cli
+			$router_path = WP_CLI_ROOT . '/../../../router.php';
 			if ( ! file_exists( $router_path ) ) {
 				WP_CLI::error( "Couldn't find router.php" );
 			}