Allow to blacklist tests only in CI

Currently there is no way to black list a test only in the CI system.
The result is that many tests are failing only on CI, and the fix is to blacklist them.
Meaning that they will be blacklisted also for non CI platforms, where the test is supposed to run.

In this way it's going to be harder to catch real failures of the test, failures that could be reproduced on normal machines.

Having this option would allow to temporarily blacklists tests only on CI, but still keep them running locally, improving their capacity of catching problems if some regression is going to be introduced