Incrementing stack template registry version

Author: ymao1

x-pack/plugin/stack/src/main/java/org/elasticsearch/xpack/stack/StackTemplateRegistry.java

@@ -38,7 +38,7 @@ public class StackTemplateRegistry extends IndexTemplateRegistry {
 
     // The stack template registry version. This number must be incremented when we make changes
     // to built-in templates.
-    public static final int REGISTRY_VERSION = 14;
+    public static final int REGISTRY_VERSION = 15;
 
     public static final String TEMPLATE_VERSION_VARIABLE = "xpack.stack.template.version";
     public static final Setting<Boolean> STACK_TEMPLATES_ENABLED = Setting.boolSetting(