Add post job to build canary build on latest master Add unit test to restrict usage of secrets
Add post job to build canary build on latest master
Add unit test to restrict usage of secrets

GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid,GoogleCloudPlatform/testgrid