Fix bug in Dockerfile of Twine Cloud Builder
Fix bug in Dockerfile of Twine Cloud Builder

google-octo/cloud-builders,google-octo/cloud-builders,GoogleCloudPlatform/cloud-builders,GoogleCloudPlatform/cloud-builders,google-octo/cloud-builders,google-octo/cloud-builders,GoogleCloudPlatform/cloud-builders,google-octo/cloud-builders,google-octo/cloud-builders,GoogleCloudPlatform/cloud-builders,GoogleCloudPlatform/cloud-builders,GoogleCloudPlatform/cloud-builders,google-octo/cloud-builders,GoogleCloudPlatform/cloud-builders