[elasticsearch] improve pvc purge

`release` label need to be added StatefulSet `spec.selector.matchLabels` to be included in pvc so we can select only pvc matching release

elasticsearch/examples/6.x/Makefile

@@ -13,4 +13,4 @@ test: install goss
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/config/Makefile

@@ -17,4 +17,4 @@ test: secrets install goss
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/default/Makefile

@@ -14,4 +14,4 @@ test: install goss
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/docker-for-mac/Makefile

@@ -10,4 +10,4 @@ test: install
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/kubernetes-kind/Makefile

@@ -10,4 +10,4 @@ test: install
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/minikube/Makefile

@@ -10,4 +10,4 @@ test: install
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/multi/Makefile

@@ -14,4 +14,5 @@ test: install goss
 purge:
 	helm del --purge $(PREFIX)-master
 	helm del --purge $(PREFIX)-data
-	for pvc in $$(kubectl get pvc -o name | grep $(PREFIX)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(PREFIX)-master -o name)
+	kubectl delete $$(kubectl get pvc -l release=$(PREFIX)-data -o name)

elasticsearch/examples/openshift/Makefile

@@ -13,4 +13,4 @@ test: install goss
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/oss/Makefile

@@ -10,4 +10,4 @@ test: install goss
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/examples/security/Makefile

@@ -10,7 +10,7 @@ install:
 purge:
 	kubectl delete secrets elastic-credentials elastic-certificates elastic-certificate-pem || true
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)
 
 test: secrets install goss
 

elasticsearch/examples/upgrade/Makefile

@@ -23,4 +23,4 @@ test: init install goss
 
 purge:
 	helm del --purge $(RELEASE)
-	for pvc in $$(kubectl get pvc -o name | grep $(RELEASE)); do kubectl delete $$pvc; done
+	kubectl delete $$(kubectl get pvc -l release=$(RELEASE) -o name)

elasticsearch/templates/statefulset.yaml

@@ -18,6 +18,7 @@ spec:
   selector:
     matchLabels:
       app: "{{ template "uname" . }}"
+      release: {{ .Release.Name | quote }}
   replicas: {{ .Values.replicas }}
   podManagementPolicy: {{ .Values.podManagementPolicy }}
   updateStrategy: