process: changed var to const in internal/process/promises

PR-URL: #8620
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Jackson Tian <[email protected]>
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Ilkka Myller <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>

lib/internal/process/promises.js

@@ -25,7 +25,7 @@ function setupPromises(scheduleMicrotasks) {
   }
 
   function rejectionHandled(promise) {
-    var hasBeenNotified = hasBeenNotifiedProperty.get(promise);
+    const hasBeenNotified = hasBeenNotifiedProperty.get(promise);
     if (hasBeenNotified !== undefined) {
       hasBeenNotifiedProperty.delete(promise);
       const uid = promiseToGuidProperty.get(promise);