v8: Copyright: Remove extra slashes

Change-Id: I3d3b1f0b86714e0d654ed18c055d394002dbec2c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3650832
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80582}

test/mjsunit/es9/object-rest-basic.js

-// // Copyright 2016 the V8 project authors. All rights reserved.
-// // Use of this source code is governed by a BSD-style license that can be
-// // found in the LICENSE file.
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
 var { ...x } = { a: 1 };
 assertEquals({ a: 1 }, x);