fix: Use gcr.io/jenkinsxio for nginx-ingress-controller image

Now that we've got a cronjob syncing
quay.io/kubernetes-ingress-controller/nginx-ingress-controller to
gcr.io/jenkinsxio/nginx-ingress-controller twice a day (via
https://github.com/jenkins-x/environment-tekton-weasel-dev/pull/602),
let's pull the trigger and use that image repo.

fixes jenkins-x/jx#7256

Signed-off-by: Andrew Bayer <andrew.bayer@gmail.com>

Author: abayer

systems/jxing/values.tmpl.yaml

@@ -1,5 +1,7 @@
 nginx-ingress:
   controller:
+    image:
+      repository: gcr.io/jenkinsxio/nginx-ingress-controller
     replicaCount: 3
     extraArgs:
       publish-service: kube-system/jxing-nginx-ingress-controller