Clean up src/wasm and test/

Bug: v8:11074
Change-Id: I1b3d3475a0fbfafe75bb49acfd851f8bd5af5182
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2519183Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71025}