return empty nodeips during chart rendering dry-run (#5760)

Signed-off-by: Abhishek Pandey <abhpandey@microsoft.com>

Author: abhishek-pandey-1

charts/kube-ovn-v2/templates/_helpers.tpl

@@ -55,10 +55,12 @@ Create the name of the service account to use
 
 
 {{/*
-Get IP-addresses of master nodes
+Get IP-addresses of master nodes. If no nodes are returned, we assume this is
+a dry-run/template call and return nothing.
 */}}
 {{- define "kubeovn.nodeIPs" -}}
 {{- $nodes := lookup "v1" "Node" "" "" -}}
+{{- if $nodes -}}
 {{- $ips := list -}}
 {{- range $node := $nodes.items -}}
   {{- range $label, $value := $.Values.masterNodesLabels }}
@@ -77,6 +79,7 @@ Get IP-addresses of master nodes
 {{- end -}}
 {{ join "," $ips }}
 {{- end -}}
+{{- end -}}
 
 {{/*
 Number of master nodes

charts/kube-ovn/templates/_helpers.tpl

@@ -1,8 +1,10 @@
 {{/*
-Get IP-addresses of master nodes
+Get IP-addresses of master nodes. If no nodes are returned, we assume this is
+a dry-run/template call and return nothing.
 */}}
 {{- define "kubeovn.nodeIPs" -}}
 {{- $nodes := lookup "v1" "Node" "" "" -}}
+{{- if $nodes -}}
 {{- $ips := list -}}
 {{- range $node := $nodes.items -}}
   {{- $label := splitList "=" $.Values.MASTER_NODES_LABEL }}
@@ -25,6 +27,7 @@ Get IP-addresses of master nodes
 {{- end -}}
 {{ join "," $ips }}
 {{- end -}}
+{{- end -}}
 
 {{/*
 Number of master nodes