Ingress: k8s and ingress version compatibility

k8s 1.14 first enabled Ingress in the networking.k8s.io/v1beta1 API
group, while still serving it in the extensions/v1beta1 API group. The
extensions/v1beta1 API endpoint is deprecated in 1.16 and scheduled for
removal in 1.20. [0]

ingress-nginx 0.25.0 actually uses the networking.k8s.io/v1beta1 API,
which requires updated RBAC rules. [1]

This change updates the ClusterRole used by the ingress service account
to grant access to Ingress resources via either the extensions/v1beta1
or networking.k8s.io/v1beta1 API, aligning with the static manifests
from the kubernetes/ingress-nginx repo [2]. It does not change the
apiVersion used when creating Ingress resources.

[0] https://kubernetes.io/blog/2019/07/18/api-deprecations-in-1-16/
[1] https://github.com/kubernetes/ingress-nginx/releases/tag/nginx-0.25.0
[2] 870be3bcd8/deploy/static/mandatory.yaml (L50-L106)

Change-Id: I67d4dbdb3834ca4ac8ce90ec51c8d6414ce80a01

ingress/templates/deployment-ingress.yaml

@@ -58,21 +58,22 @@ rules:
       - get
       - list
       - watch
+  - apiGroups:
+      - ""
+    resources:
+      - events
+    verbs:
+      - create
+      - patch
   - apiGroups:
       - "extensions"
+      - "networking.k8s.io"
     resources:
       - ingresses
     verbs:
       - get
       - list
       - watch
-  - apiGroups:
-      - ""
-    resources:
-        - events
-    verbs:
-        - create
-        - patch
   - apiGroups:
       - "extensions"
       - "networking.k8s.io"