Better Test Wiring Support for ConfigurationProperties

[jdaugherty]

I have a ServiceUnitTest that is failing because on my Grails Service, I'm injecting an object annotated with @ConfigurationProperties(PREFIX) and the bean isn't being defined by the ServiceUnitTest.

Plugins like grails-mail have moved to configurationProperties so we should consider adding better support in our test framework to autowire these in unit tests.