Stream test output on Windows CI

script/cibuild

@@ -86,8 +86,6 @@ def main():
     run_script('create-dist.py')
     run_script('upload.py')
   else:
-    if PLATFORM == 'win32':
-      os.environ['OUTPUT_TO_FILE'] = 'output.log'
     run_script('build.py', ['-c', 'D'])
     if PLATFORM == 'win32' or target_arch == 'x64':
       run_script('test.py', ['--ci'])