Always return an empty string when formatting stack traces with
--correctness-fuzzer-suppressions. In out-of-stack-space situations
it's easy to get different values depending on whether emergency
formatting is chosen or not.

Bug: chromium:1244626
Change-Id: I2f3d1692deae2533b70b62f28b39875e812b4b0c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3132968Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76609}