lib: unnecessary const assignment for class

PR-URL: #32962
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Andrey Pechkurov <apechkurov@gmail.com>

lib/internal/fixed_queue.js

@@ -56,7 +56,7 @@ const kMask = kSize - 1;
 // `top + 1 === bottom` it's full. This wastes a single space of storage
 // but allows much quicker checks.
 
-const FixedCircularBuffer = class FixedCircularBuffer {
+class FixedCircularBuffer {
   constructor() {
     this.bottom = 0;
     this.top = 0;
@@ -85,7 +85,7 @@ const FixedCircularBuffer = class FixedCircularBuffer {
     this.bottom = (this.bottom + 1) & kMask;
     return nextItem;
   }
-};
+}
 
 module.exports = class FixedQueue {
   constructor() {