Expose MustBeClosedChecker exception

[uhafner]

No description provided.

[github-actions]

🎓 Quality Checks - 200 of 400

🚦 JUnit - 100 of 100

0 tests passed

🐾 JaCoCo - 0 of 100

0% Covered , 100% Missed

🦠 PIT - 0 of 100

0% Killed , 100% Survived

⚠️ Warnings - 100 of 100

no warnings found

🚧 Error Messages

Autograding GitHub Action Errors:
No matching report files found when using pattern '**/target/*-reports/TEST*.xml'! Configuration error for 'Unittests'?
No matching report files found when using pattern '**/target/site/jacoco/jacoco.xml'! Configuration error for 'Line Coverage'?
No matching report files found when using pattern '**/target/site/jacoco/jacoco.xml'! Configuration error for 'Branch Coverage'?
No matching report files found when using pattern '**/target/pit-reports/mutations.xml'! Configuration error for 'Mutation Coverage'?
No matching report files found when using pattern '**/target/checkstyle-result.xml'! Configuration error for 'CheckStyle'?
No matching report files found when using pattern '**/target/pmd.xml'! Configuration error for 'PMD'?
No matching report files found when using pattern '**/target/spotbugsXml.xml'! Configuration error for 'SpotBugs'?

More details are available in the GitHub Checks Result.