api: test: Supply --out-dir to build-dockerimages.py

Chroot state is starting to get pulled out to an output directory, so we
need to supply out-dir as an argument now.

BUG=b:265885353
TEST=./run_tests

Cq-Depend: chromium:4617188
Change-Id: I4c975d669d90c7090dab3c5922791f013f608e24
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4618378
Auto-Submit: Brian Norris <briannorris@chromium.org>
Reviewed-by: Lizzy Presland <zland@google.com>
Commit-Queue: Lizzy Presland <zland@google.com>
Reviewed-by: Derek Beckett <dbeckett@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
diff --git a/api/controller/test_unittest.py b/api/controller/test_unittest.py
index a738f5e..543b666 100644
--- a/api/controller/test_unittest.py
+++ b/api/controller/test_unittest.py
@@ -386,7 +386,7 @@
 
     def setUp(self):
         self.request = test_pb2.BuildTestServiceContainersRequest(
-            chroot={"path": "/path/to/chroot"},
+            chroot={"path": "/path/to/chroot", "out_path": "/path/to/out"},
             build_target={"name": "build_target"},
             version="R93-14033.0.0",
         )