Delete button for assignment is visible to students
# Summary
<!--Describe the bug in short here. Describe what happens that is considered
bad behaviour.-->
As a student I can see the delete button next to an assignment in the modules overview.

# Steps to reproduce
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is preferred to be able to easily reproduce.-->
1. Open a lab
2. Go to the modules tab
# Possible Fix
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think is going wrong.-->
# Logs
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issue