[stable/prestashop] Fix chart not being upgradable (#7843)

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

stable/prestashop/Chart.yaml

@@ -1,5 +1,5 @@
 name: prestashop
-version: 2.0.8
+version: 3.0.0
 appVersion: 1.7.4-2
 description: A popular open source ecommerce solution. Professional tools are easily
   accessible to increase online sales including instant guest checkout, abandoned

stable/prestashop/README.md

@@ -137,3 +137,15 @@ The [Bitnami PrestaShop](https://github.com/bitnami/bitnami-docker-prestashop) i
 
 Persistent Volume Claims are used to keep the data across deployments. This is known to work in GCE, AWS, and minikube.
 See the [Configuration](#configuration) section to configure the PVC or to disable persistence.
+
+## Upgrading
+
+### To 3.0.0
+
+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 3.0.0. The following example assumes that the release name is prestashop:
+
+```console
+$ kubectl patch deployment prestashop-prestashop --type=json -p='[{"op": "remove", "path": "/spec/selector/matchLabels/chart"}]'
+$ kubectl delete statefulset prestashop-mariadb --cascade=false
+```

stable/prestashop/templates/deployment.yaml

@@ -9,6 +9,10 @@ metadata:
     release: "{{ .Release.Name }}"
     heritage: "{{ .Release.Service }}"
 spec:
+  selector:
+    matchLabels:
+      app: {{ template "prestashop.fullname" . }}
+      release: "{{ .Release.Name }}"
   template:
     metadata:
       labels: