The tests for property access on builder parameters now use BeanHelper.

Due to the specially configured BeanUtilsBean instance managed by BeanHelper,
it is able to set properties on objects which do not fully comply to the Java
Beans specification.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/configuration/trunk@1553024 13f79535-47bb-0310-9956-ffa450edef68