cli/scripts: more cros_build_lib.run API migrations

BUG=b:187789262
TEST=CQ passes

Change-Id: Idcc78ccfe14fdbae89ae7573d6e78036bdacf8ad
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/3738519
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Ram Chandrasekar <rchandrasekar@google.com>
Auto-Submit: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Ram Chandrasekar <rchandrasekar@google.com>
diff --git a/scripts/pushimage_unittest.py b/scripts/pushimage_unittest.py
index dd56d7d..8ed07bb 100644
--- a/scripts/pushimage_unittest.py
+++ b/scripts/pushimage_unittest.py
@@ -341,7 +341,7 @@
   def testGsError(self):
     """Verify random GS errors don't make us blow up entirely"""
     self.gs_mock.AddCmdResult(partial_mock.In('stat'), returncode=1,
-                              output='gobblety gook\n')
+                              stdout='gobblety gook\n')
     with cros_test_lib.LoggingCapturer('chromite'):
       self.assertRaises(pushimage.PushError, pushimage.PushImage, '/src',
                         'test.board', 'R34-5126.0.0')