Correctly handle rejected jobs in export

On the current Batsim when a job gets rejected it is not marked as completed and thus Batsim crashes during the export of that job.

Pipeline

Checklist

Branch name.

• Descriptive and short
• Use hyphens to separate words

Branch content.

• Only dedicated to the problem.
• Based on Batsim's official master branch.
• Straightforward. Just a sequence of commits. Does not contain merge commits.
• Test results are not worse than before.