Fix broken binhost_test.py.

Fix broken binhost_test.py which was broken by the removals in
https://crrev.com/c/1906530. The test remains in place as it is pointed
at by some COMMIT-QUEUE.ini but no longer tests anything.

TEST=./run_tests
TEST=./cbuildbot/binhost_test
BUG=chromium:1021398

Change-Id: I685fbd734870d9a6f1a91e81bf58c83b689c1157
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1911141
Reviewed-by: Andrew Lamb <andrewlamb@chromium.org>
Commit-Queue: David Burger <dburger@chromium.org>
Tested-by: David Burger <dburger@chromium.org>
diff --git a/cbuildbot/binhost_test.py b/cbuildbot/binhost_test.py
index aeb158e..67c08c6 100644
--- a/cbuildbot/binhost_test.py
+++ b/cbuildbot/binhost_test.py
@@ -7,6 +7,8 @@
 
 from __future__ import print_function
 
+from chromite.lib import cros_test_lib
+
 
 class PrebuiltCompatibilityTest(cros_test_lib.TestCase):
   """Ensure that prebuilts are present for all builders and are compatible."""