correctly set payload for renamed shape in codegen

Author: sbiscigl

tools/code-generation/generator/src/main/java/com/amazonaws/util/awsclientgenerator/transform/C2jModelToGeneratorModelTransformer.java

@@ -809,7 +809,7 @@ void renameReservedFields(Shape shape) {
                             member.getShape().getName(),
                             reservedMapping.getValue().remappingName,
                             member.getShape().getName(),
-                            false);
+                            reservedMapping.getKey().equals(shape.getPayload()));
                 });
         }
     }