title: Adding properties to JHipster Cloud application.yml causes registry configuration to fail
body: <p>I want to add a custom property to the <code>application.yml</code> of my Cloud Config. The comments in the file say it is for all shared configuration. However, when I do so, it causes the binding of the properties to JHipsters own ApplicationProperties to fail at the class does not have the correct writable property.</p>
  
  <p>application.yml</p>
  
  <pre><code>application:
      clients:
          - Foo
  </code></pre>
  
  <p>Stacktrace:</p>
  
  <pre><code>Caused by: org.springframework.boot.bind.RelaxedBindingNotWritablePropertyException: Failed to bind 'application.clients[0]' from 'file:central-config/localhost-config/application.yml' to 'clients[0]' property on 'io.github.jhipster.registry.config.ApplicationProperties'
  </code></pre>