[Fleet] Add hidden property to fleet enrollment api keys

Author: nchaulet

x-pack/plugin/core/template-resources/src/main/resources/fleet-enrollment-api-keys.json

@@ -36,6 +36,9 @@
         },
         "namespaces": {
           "type": "keyword"
+        },
+        "hidden": {
+          "type": "boolean"
         }
       }
     }

x-pack/plugin/fleet/src/main/java/org/elasticsearch/xpack/fleet/Fleet.java

@@ -80,7 +80,7 @@ public class Fleet extends Plugin implements SystemIndexPlugin {
     private static final List<String> ALLOWED_PRODUCTS = List.of("kibana", "fleet");
     private static final int FLEET_ACTIONS_MAPPINGS_VERSION = 2;
     private static final int FLEET_AGENTS_MAPPINGS_VERSION = 2;
-    private static final int FLEET_ENROLLMENT_API_KEYS_MAPPINGS_VERSION = 2;
+    private static final int FLEET_ENROLLMENT_API_KEYS_MAPPINGS_VERSION = 3;
     private static final int FLEET_SECRETS_MAPPINGS_VERSION = 1;
     private static final int FLEET_POLICIES_MAPPINGS_VERSION = 2;
     private static final int FLEET_POLICIES_LEADER_MAPPINGS_VERSION = 1;