v8: Copyright: Remove extra slashes

Change-Id: Ib8ca0c771b50b712e5fd6acb470213235f69a99b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3650833Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Solomon Kinard <solomonkinard@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80569}

test/mjsunit/regress/wasm/regress-1074586-b.js

 // Copyright 2020 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.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
 // Flags: --wasm-staging