Polish RecordBeanParamExtractor

Author: geoand

independent-projects/resteasy-reactive/server/runtime/src/main/java/org/jboss/resteasy/reactive/server/core/parameters/RecordBeanParamExtractor.java

@@ -9,7 +9,7 @@
 
 public class RecordBeanParamExtractor implements ParameterExtractor {
 
-    private MethodHandle factoryMethod;
+    private final MethodHandle factoryMethod;
 
     public RecordBeanParamExtractor(Class<?> target) {
         try {