fix(helm): delete needless labels for helm upgrade

deploy/charts/emqx/templates/StatefulSet.yaml

@@ -18,7 +18,6 @@ spec:
         namespace: {{ .Release.Namespace }}
         labels:
           app.kubernetes.io/name: {{ include "emqx.name" . }}
-          helm.sh/chart: {{ include "emqx.chart" . }}
           app.kubernetes.io/instance: {{ .Release.Name }}
           app.kubernetes.io/managed-by: {{ .Release.Service }}
       spec: