TearDown was actually redundant and can be replaced with the dtor.

Bug: v8:12612
Change-Id: Idc4a77c3f20372a53b0003cda6fb00ae7ec0035c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3571806Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79819}