fix imports

src/main/java/org/codelibs/fess/api/json/JsonApiManager.java

@@ -59,8 +59,6 @@ import org.codelibs.fess.util.EsUtil;
 import org.codelibs.fess.util.FacetResponse;
 import org.codelibs.fess.util.FacetResponse.Field;
 import org.dbflute.optional.OptionalThing;
-import org.elasticsearch.common.xcontent.ToXContent;
-import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.script.Script;
 import org.slf4j.Logger;