lib: replace var with let in loaders.js

PR-URL: #28081
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Trivikram Kamat <[email protected]>
Reviewed-By: Rich Trott <[email protected]>
Reviewed-By: Anto Aravinth <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Ruben Bridgewater <[email protected]>
Reviewed-By: Michael Dawson <[email protected]>

Author: mbj36

lib/internal/bootstrap/loaders.js

@@ -174,7 +174,7 @@ const {
 } = internalBinding('native_module');
 
 NativeModule.map = new Map();
-for (var i = 0; i < moduleIds.length; ++i) {
+for (let i = 0; i < moduleIds.length; ++i) {
   const id = moduleIds[i];
   const mod = new NativeModule(id);
   NativeModule.map.set(id, mod);