fix broken GCE-GKE service descriptor

[unthought]

fixes #1546

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[k8s-reviewable]

This change is 

[coveralls]

Coverage increased (+0.04%) to 33.454% when pulling 489b851 on unthought:unthought/fix-gce-gke-service into e4d5378 on kubernetes:master.

[aledbf]

/lgtm

[aledbf]

@unthought thanks!