Slimmer docker tool builder.
Slimmer docker tool builder.

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MOE_MIGRATED_REVID=128485642
APPROVED=

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