[clang-tidy] Add override to overridden destructors

See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-override.html
for more on this warning.

Bug: v8:10488
Change-Id: I78fdfb904ea94d9ae034b41cd43be8689a0096ea
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2211188
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67985}

src/compiler/memory-lowering.h

@@ -78,7 +78,6 @@ class MemoryLowering final : public Reducer {
       WriteBarrierAssertFailedCallback callback = [](Node*, Node*, const char*,
                                                      Zone*) { UNREACHABLE(); },
       const char* function_debug_name = nullptr);
-  ~MemoryLowering() = default;
 
   const char* reducer_name() const override { return "MemoryReducer"; }