Functions: clarify cloudbuild.yaml (#2946)
Functions: clarify cloudbuild.yaml (#2946)

cc @labtopia @saturnism
GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples