There is now only one invocation left of
MemoryAllocator::Unmapper::FreeQueuedChunks in the GC epilogue.

Bug: chromium:1329064, chromium:1327132
Change-Id: Icc21ada4c5a8a9505ed6435ef1f62fe48b2dbb52
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3667079
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80745}