[iOS][test runner] Remove outputting compiled tests default arg.

This is to unblock a Chromium roll into WebRTC which complains that the
arg can't be recognized.

The task to add back the arg to some builder configs is tracked at:
crbug/1092583.

Bug: 1097093
Change-Id: Ia006723d85630f2b07c8e8207bfe436ac7a37cfd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2258415Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Zhaoyang Li <zhaoyangli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#781087}

ios/build/bots/scripts/test_apps.py

@@ -105,9 +105,6 @@ class GTestsApp(object):
     self.test_app_path = test_app
     self.project_path = os.path.dirname(self.test_app_path)
     self.test_args = test_args or []
-    # TODO(crbug.com/1092583): Move this switch as a test variant running only
-    # in selected builder that should output disabled tests.
-    self.test_args.append('--write-compiled-tests-json-to-writable-path')
     self.env_vars = {}
     for env_var in env_vars or []:
       env_var = env_var.split('=', 1)