[bitnami/zookeeper] Only specify JVMFLAGS env var if they are provided

Signed-off-by: tompizmor <tompizmor@gmail.com>

bitnami/zookeeper/Chart.yaml

@@ -1,5 +1,5 @@
 name: zookeeper
-version: 1.2.0
+version: 1.2.1
 appVersion: 3.4.12
 description: A centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services for distributed applications.
 keywords:

bitnami/zookeeper/templates/statefulset.yaml

@@ -119,8 +119,10 @@ spec:
         {{- else }}
           value: "no"
         {{- end }}
+        {{- if .Values.jvmFlags }}
         - name: JVMFLAGS
           value: {{ .Values.jvmFlags | quote }}
+        {{- end }}
         ports:
         - name: client
           containerPort: {{ .Values.service.port }}