payload_utils: Change all imports from "bindings" to "config".

- Make all imports consistent.

BUG=None
TEST=CQ

Change-Id: I036caa6be8214d625d4976bab841f7617a585020
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/config/+/2145033
Reviewed-by: David Burger <dburger@chromium.org>
Commit-Queue: Andrew Lamb <andrewlamb@chromium.org>
Tested-by: Andrew Lamb <andrewlamb@chromium.org>
diff --git a/payload_utils/checker/io_utils_test.py b/payload_utils/checker/io_utils_test.py
index 717ff92..7f9b7d9 100644
--- a/payload_utils/checker/io_utils_test.py
+++ b/payload_utils/checker/io_utils_test.py
@@ -9,8 +9,8 @@
 
 from checker import io_utils
 
-from bindings.payload.config_bundle_pb2 import ConfigBundle
-from bindings.api.program_pb2 import ProgramList, Program
+from config.payload.config_bundle_pb2 import ConfigBundle
+from config.api.program_pb2 import ProgramList, Program
 
 
 class IoUtilsTest(unittest.TestCase):