Exclude samples for interactive problems.

[eldering]

(cherry picked from commit 0cc0da082f9d96a0cc653755d4e22fb837a3c84d)

[sentry-io[bot]]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: webapp/src/Service/DOMJudgeService.php

Function	Unhandled Issue
App\Service\DOMJudgeService::getSamplesZipForContest	Doctrine\ORM\NoResultException: No result was found for query although at least one row was expected. /src/Service/DOMJudgeService.php in... Event Count: 2

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[Kevinjil]

Wouldn't it be nicer if we do not allow downloading a sample zip for interactive problems, instead of supplying an empty zip?

[meisterT]

This code path is the overall zip with all samples, and we still include the attachments, so it is not empty.