Add an integration test checking the workingdirs
Add an integration test checking the workingdirs

We didn't check previously if workingdir step really worked properly.

The workingdir container steps is taking care to make sure the workingdir
directory is created into the workspace,

Signed-off-by: Chmouel Boudjnah <62677a06b3e78665bfcc28953f542f81f478cf54@redhat.com>

tektoncd/pipeline,tektoncd/pipeline