Add maintenance jobs for integration-scripts

The module at https://github.com/nuxeo/integration-scripts is covered by CI at https://qa.nuxeo.org/jenkins/job/master/job/tools_integration-scripts-master/

This module is needed by maintenance jobs, so it should be covered by CI too, so that changes done for NXBT-1403 can be directly referenced in the jira issue.

Some of these changes are recurrent, at each HF release (for instance https://github.com/nuxeo/integration-scripts/commit/f66c0878e8d7179457d509407fae154982315287)

It would also be good to decide what jira project follows this tooling (NXBT?) as a lot of different jira projects are used in commit messages (NXP, NXBT, and also none)