Workbench Rest API - deleting space sometimes randomly takes more than 10-30 seconds

There is a couple of integration tests in kie-wb-distributions that test workbench rest api (managing projects, spaced, maven build etc.).

These have been failing very often as described in this PR. For example failure see this.

We found that they're failing in the step when spaces are deleted in `@AfterClass` - quite often it takes more than 10 seconds to delete the space and the client request times out. This seems to be happening randomly no matter the size of space being deleted (even space with just 1 empty project).

For now I increased client timeout to 30 seconds, so that these tests don't fail so often.

TODO the goal of this task is to find the root cause of the slowness. To make the investigation easier I create an `@Ignore`-d test in the PR above which, when disabled, clearly demonstrates this behavior.