lib: change var to let/const

Author: rene.herrmann

lib/internal/console/constructor.js

@@ -115,12 +115,11 @@ function Console(options /* or: stdout, stderr, ignoreErrors = true */) {
 
   // Bind the prototype functions to this Console instance
   const keys = ObjectKeys(Console.prototype);
-  for (var v = 0; v < keys.length; v++) {
-    var k = keys[v];
+  for (const key of keys) {
     // We have to bind the methods grabbed from the instance instead of from
     // the prototype so that users extending the Console can override them
     // from the prototype chain of the subclass.
-    this[k] = this[k].bind(this);
+    this[key] = this[key].bind(this);
   }
 
   this[kBindStreamsEager](stdout, stderr);