We used to expose raw WasmGC objects via the JS interface and made
use of that in our cctests. Since those objects would cause crashes
when used in JavaScript, this patch prevents such interactions, and
migrates the tests to use the C-Wasm interface instead.

Bug: v8:7748
Change-Id: I76a10663cda43c940c8c22c57c14922be9b05134
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2284497
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68725}