Fix find open test-case failure in Gitlab issues

To append new comments in to same test-case failure the application checks for open issues with the test-failure label. However, by default only the last 20 are returned.

In order to properly find an open test-case failure in Gitlab issues, retrieve all the open issues.

https://phabricator.apertis.org/T8618

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