[trials] Remove unnecessary flag

No-Try: true
Bug: chromium:1340816
Change-Id: Ic49c5e00a90085b575465bbb463645977ee1d34b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3768987
Auto-Submit: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81837}

tools/clusterfuzz/trials/clusterfuzz_trials_config.json

@@ -35,5 +35,5 @@
     {"app_args": "--stress-scavenge=100", "app_name": "d8", "probability": 0.05},
     {"app_args": "--turbo-instruction-scheduling", "app_name": "d8", "probability": 0.1},
     {"app_args": "--turbo-stress-instruction-scheduling", "app_name": "d8", "probability": 0.1},
-    {"app_args": "--wasm-code-gc --stress-wasm-code-gc", "app_name": "d8", "probability": 0.1}
+    {"app_args": "--stress-wasm-code-gc", "app_name": "d8", "probability": 0.1}
 ]