Clear failed action name when the failed flag is cleared

[jowerner]

If an error occurred in a test scenario, XLT marks the current session as failed. As a side effect, it also sets the name of the current action as the failed action name at the session. So far, so good.

The test scenario may decide to ignore that error. To this end, it typically catches exceptions and resets the failed at the session. However, the failed action name cannot be reset at the moment. Should the test scenario fail again later on (not ignored that time), then the exception is correctly reported, but the name of the failing action is wrong, i.e. it is the one from the first error.

In order to solve this issue, the failed action name at the session should be cleared whenever the failed flag is cleared by the scenario via Session.getCurrent().setFailed(false).