[testrunner] remove duplicate word from prompt

R=clemensh@chromium.org
CC=machenbach@chromium.org,sergiyb@chromium.org

Bug: v8:8728
Change-Id: I37d10867a805647c98660699233c5c2b23429eae
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1503377Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Sergiy Belozorov <sergiyb@chromium.org>
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60038}

tools/testrunner/standard_runner.py

@@ -329,7 +329,7 @@ class StandardTestRunner(base_runner.BaseTestRunner):
       else:
         percentage = 0
 
-      print (('>>> %d base tests produced %d tests (%d%s)'
+      print (('>>> %d base tests produced %d (%d%s)'
              ' non-filtered tests') % (
           tests.test_count_estimate, results.total, percentage, '%'))