The test allocates a lot of wasm memories. This got a low slower after
https://crrev.com/c/3190476, because we can now allocate more than 102
memories, and do not explicitly trigger a GC any more to get rid of
unused memories.
We should figure out how to tell the GC about the external memory such
that the memories get collected earlier.

R=ahaas@chromium.org

Bug: v8:12076, v8:12278
Change-Id: I9b8795a9999a806380d86f22e751de2727942648
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3196131Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77164}