[stable/nats] Fix chart not being upgradable (#7832)

Signed-off-by: Javier J. Salmeron Garcia <jsalmeron@bitnami.com>

stable/nats/Chart.yaml

@@ -1,5 +1,5 @@
 name: nats
-version: 0.1.1
+version: 1.0.0
 appVersion: 1.3.0
 description: An open-source, cloud-native messaging system
 keywords:

stable/nats/README.md

@@ -163,3 +163,14 @@ To horizontally scale this chart, run the following command to scale the number
 ```console
 $ kubectl scale statefulset my-release-nats --replicas=3
 ```
+
+## Upgrading
+
+### To 1.0.0
+
+Backwards compatibility is not guaranteed unless you modify the labels used on the chart's deployments.
+Use the workaround below to upgrade from versions previous to 1.0.0. The following example assumes that the release name is nats:
+
+```console
+$ kubectl delete statefulset nats-nats --cascade=false
+```

stable/nats/templates/statefulset.yaml

@@ -19,7 +19,6 @@ spec:
   selector:
     matchLabels:
       app: "{{ template "nats.name" . }}"
-      chart: "{{ template "nats.chart" . }}"
       release: {{ .Release.Name | quote }}
   template:
     metadata: