Update saltstack example templates to use updated image family
Update saltstack example templates to use updated image family

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=149063689

aljim/deploymentmanager-samples,jaivasanth-google/deploymentmanager-samples,aljim/deploymentmanager-samples,GoogleCloudPlatform/deploymentmanager-samples,GoogleCloudPlatform/deploymentmanager-samples,aljim/deploymentmanager-samples,aljim/deploymentmanager-samples,jaivasanth-google/deploymentmanager-samples,GoogleCloudPlatform/deploymentmanager-samples