[heap] Delete skipped test

Test was already skipped for quite some time.

Bug: v8:8169
Change-Id: I1cb4f024e43a42c48b425ad0c713fb85bbfb2354
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3762580Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81727}

test/mjsunit/external-backing-store-gc.js

-// Copyright 2018 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.
-
-// Flags: --mock-arraybuffer-allocator --mock-arraybuffer-allocator-limit=1300000000
-
-// --mock-arraybuffer-allocator-limit should be above the hard limit external
-// for memory. Below that limit anything is opportunistic and may be delayed,
-// e.g., by tasks getting stalled and the event loop not being invoked.
-
-for (var i = 0; i < 1536; i++) {
-  let garbage = new ArrayBuffer(1024*1024);
-}

test/mjsunit/mjsunit.status

@@ -69,9 +69,6 @@
   # https://crbug.com/v8/7775
   'allocation-site-info': [SKIP],
 
-  # BUG(v8:8169)
-  'external-backing-store-gc': [SKIP],
-
   # BUG(v8:10197)
   'regress/regress-748069': [SKIP],