[COMMON][MARIADB] Corrected PeerAuthentication matchLabels

The matchLabels should use the existing Label:
app.kubernetes.io/name instead of adding a new label

Issue-ID: OOM-2820

Signed-off-by: Andreas Geissler <andreas-geissler@telekom.de>
Change-Id: I9d4405f2855f34cc32085ba571478dafa344e51e
diff --git a/kubernetes/common/mariadb-galera/templates/service.yaml b/kubernetes/common/mariadb-galera/templates/service.yaml
index 880bc55..9b4c05e 100644
--- a/kubernetes/common/mariadb-galera/templates/service.yaml
+++ b/kubernetes/common/mariadb-galera/templates/service.yaml
@@ -29,7 +29,7 @@
 spec:
   selector:
     matchLabels:
-      app: {{ include "common.servicename" . }}
+      app.kubernetes.io/name: {{ include "common.servicename" . }}
   portLevelMtls:
     {{ .Values.service.internalPort }}:
       mode: DISABLE