Use gke-gcloud-auth-plugin in /.deploystack/test (#1512)

.deploystack/test

@@ -88,7 +88,7 @@ function generateProject(){
     local __DATELABEL=$(date +%F)
     local VALUE=ds-test-$__STACKSUFFIX-$__RANDOMSUFFIX
     local __BA=$(gcloud beta billing accounts list --format="value(ACCOUNT_ID)" --limit=1 | xargs)
-   
+
     gcloud projects create $VALUE --labels="deploystack-disposable-test-project=$__DATELABEL" --folder="155265971980"
     gcloud beta billing projects link $VALUE --billing-account=$__BA
     eval $__resultvar="'$VALUE'"
@@ -104,6 +104,10 @@ section_open "Generate random test project"
     generateProject PROJECT "$suffix"
 section_close
 
+# We need to force the use of gke-gcloud-auth-plugin (for GKE authentication)
+# if we're using kubectl 1.25 or lower.
+export USE_GKE_GCLOUD_AUTH_PLUGIN=True
+
 DIR="terraform"
 gcloud services enable cloudresourcemanager.googleapis.com --project=$PROJECT
 REGION="us-central1"
@@ -162,7 +166,7 @@ section_open "Testing Google Kubernetes Engine cluster does NOT exist"
 section_close
 
 # This is only needed if you tests fail alot because of overlaping runs of the
-# same set of tests. Really don't do this if you don't want to severly irritate 
+# same set of tests. Really don't do this if you don't want to severly irritate
 # @tpryan
 section_open "Delete Test Project"
     gcloud projects delete $PROJECT -q