repl: simplify regex expression

PR-URL: nodejs#26496
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

Author: gengjiawen

lib/repl.js

@@ -1337,8 +1337,8 @@ function _memory(cmd) {
   if (cmd) {
     // Going down is { and (   e.g. function() {
     // going up is } and )
-    var dw = cmd.match(/{|\(/g);
-    var up = cmd.match(/}|\)/g);
+    let dw = cmd.match(/[{(]/g);
+    let up = cmd.match(/[})]/g);
     up = up ? up.length : 0;
     dw = dw ? dw.length : 0;
     var depth = dw - up;