Make sure that FORCE_JOB_SKIP is unset

To performs some tests FORCE_JOB_SKIP is set and unset, however, it the pipeline is cancelled by timeout it could lead to the setting to remain active, making other tests to fail.

In order to overcome the issue let's make sure that FORCE_JOB_SKIP is not set before running tests.

https://phabricator.apertis.org/T9379

Signed-off-by: Walter Lozano walter.lozano@collabora.com