Bump registry version

Author: carsonip

x-pack/plugin/monitoring/src/main/java/org/elasticsearch/xpack/monitoring/MonitoringTemplateRegistry.java

@@ -77,7 +77,7 @@ public class MonitoringTemplateRegistry extends IndexTemplateRegistry {
      * writes monitoring data in ECS format as of 8.0. These templates define the ECS schema as well as alias fields for the old monitoring
      * mappings that point to the corresponding ECS fields.
      */
-    public static final int STACK_MONITORING_REGISTRY_VERSION = 8_00_00_99 + 20;
+    public static final int STACK_MONITORING_REGISTRY_VERSION = 8_00_00_99 + 21;
     private static final String STACK_MONITORING_REGISTRY_VERSION_VARIABLE = "xpack.stack.monitoring.template.release.version";
     private static final String STACK_TEMPLATE_VERSION = "8";
     private static final String STACK_TEMPLATE_VERSION_VARIABLE = "xpack.stack.monitoring.template.version";