Make search business rules plugin extensible

Author: kderusso

x-pack/plugin/ent-search/build.gradle

@@ -17,7 +17,7 @@ base {
 
 dependencies {
   compileOnly project(path: xpackModule('core'))
-  implementation project(xpackModule('search-business-rules'))
+  compileOnly project(xpackModule('search-business-rules'))
   api project(':modules:lang-mustache')
 
   // JSON Schema dependencies

x-pack/plugin/ent-search/src/main/java/org/elasticsearch/xpack/application/EnterpriseSearch.java

@@ -24,7 +24,6 @@
 import org.elasticsearch.logging.LogManager;
 import org.elasticsearch.logging.Logger;
 import org.elasticsearch.plugins.ActionPlugin;
-import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.plugins.SearchPlugin;
 import org.elasticsearch.plugins.SystemIndexPlugin;
 import org.elasticsearch.rest.RestController;
@@ -201,6 +200,7 @@
 import org.elasticsearch.xpack.core.XPackSettings;
 import org.elasticsearch.xpack.core.action.XPackInfoFeatureAction;
 import org.elasticsearch.xpack.core.action.XPackUsageFeatureAction;
+import org.elasticsearch.xpack.searchbusinessrules.SearchBusinessRules;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -212,7 +212,7 @@
 
 import static java.util.Collections.singletonList;
 
-public class EnterpriseSearch extends Plugin implements ActionPlugin, SystemIndexPlugin, SearchPlugin {
+public class EnterpriseSearch extends SearchBusinessRules implements ActionPlugin, SystemIndexPlugin, SearchPlugin {
 
     public static final String APPLICATION_API_ENDPOINT = "_application";
 

x-pack/plugin/search-business-rules/src/main/java/org/elasticsearch/xpack/searchbusinessrules/SearchBusinessRules.java

@@ -9,6 +9,7 @@
 
 import org.elasticsearch.TransportVersion;
 import org.elasticsearch.TransportVersions;
+import org.elasticsearch.plugins.ExtensiblePlugin;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.plugins.SearchPlugin;
 import org.elasticsearch.plugins.SearchPlugin.QuerySpec;
@@ -21,7 +22,7 @@
 import static java.util.Collections.emptyList;
 import static java.util.Collections.singletonList;
 
-public class SearchBusinessRules extends Plugin implements SearchPlugin {
+public class SearchBusinessRules extends Plugin implements SearchPlugin, ExtensiblePlugin {
 
     @Override
     public List<QuerySpec<?>> getQueries() {