Fix project search d

On a maven project with multiple modules, I get the following result (found by debugging the application) :
Calling the url http://localhost:8080/jenkins/project/myProject/builds/myhash/status.json?token=111
- projectName = myProject
- item is a hudson.maven.MavenModuleSet, which make the test item instance ItemGroup<?> succeed. It happens to be also a AbstractProject (and the project we try to find).
- item.getItems() is a list of hudson.maven.MavenModule (none of them are a AbstractProject).
- resetOfPathParts.next() is "builds"
- so jenkins.getItem(resetOfPathParts.next(), item) is null.
Therefore the result is item is set to null, and the rest of the function getDynamic fail.
I fixed this issue by adding a stop condition on the loop if item is a instance of AbstractProject. I don't think of a case of a project being also a collection of projects so it might be the easier way to deal with this.