[stable/joomla] Remove distro tag (#8553)

Signed-off-by: Carlos Rodriguez Hernandez <crhernandez@bitnami.com>

stable/joomla/Chart.yaml

@@ -1,5 +1,5 @@
 name: joomla
-version: 3.3.0
+version: 3.3.1
 appVersion: 3.8.13
 description: PHP content management system (CMS) for publishing web content
 keywords:

stable/joomla/values.yaml

@@ -10,7 +10,7 @@
 image:
   registry: docker.io
   repository: bitnami/joomla
-  tag: 3.8.13-debian-9
+  tag: 3.8.13
   ## Specify a imagePullPolicy
   ## Defaults to 'Always' if image tag is 'latest', else set to 'IfNotPresent'
   ## ref: http://kubernetes.io/docs/user-guide/images/#pre-pulling-images