Increate GKE cluster upgrade timeout time to 30m

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=198322158

java/google/registry/proxy/terraform/modules/gke/cluster.tf

@@ -12,6 +12,10 @@ resource "google_container_cluster" "proxy_cluster" {
   node_version       = "${data.google_container_engine_versions.gke_version.latest_node_version}"
   min_master_version = "${data.google_container_engine_versions.gke_version.latest_master_version}"
 
+  timeouts {
+    update = "30m"
+  }
+
   node_pool {
     name               = "proxy-node-pool"
     initial_node_count = 1