fix(services) support non-None ClusterIP always (#962)

Support user-chosen ClusterIP values for all Service types so long as
the ClusterIP value is not the special "None" value.

Support the "None" value when the Service type is ClusterIP.

charts/kong/CHANGELOG.md

@@ -4,7 +4,9 @@
 
 ### Improvements
 
-* Only set `Service` `clusterIP` when `type` is `ClusterIP`
+* Only allow `None` ClusterIPs on ClusterIP-type Services.
+  [#961](https://github.com/Kong/charts/pull/961)
+  [#962](https://github.com/Kong/charts/pull/962)
 * Bumped Kong version to 3.5.
   [#957](https://github.com/Kong/charts/pull/957)
 * Support for `affinity` configuration has been added to migration job templates.

charts/kong/templates/_helpers.tpl

@@ -251,9 +251,11 @@ spec:
   {{- if .externalTrafficPolicy }}
   externalTrafficPolicy: {{ .externalTrafficPolicy }}
   {{- end }}
-  {{- if (and (eq .type "ClusterIP") .clusterIP )}}
+  {{- if .clusterIP }}
+  {{- if (or (not (eq .clusterIP "None")) (and (eq .type "ClusterIP") (eq .clusterIP "None"))) }}
   clusterIP: {{ .clusterIP }}
   {{- end }}
+  {{- end }}
   selector:
     {{- .selectorLabels | nindent 4 }}
 {{- end -}}