Completed Assignments are shown multiple times in 'Finished'

[fogti]

In an specific environment (which I don't really know, as I only know that a user-facing bug exists, which I witnessed as a non-teacher user), completed assignments are added both to 'In Progress' (correct) and to 'Finished' (incorrect, with 'never' in the 'Submitted' row). If the assignment is then later graded, it is removed from the 'In Progress' section and added to the 'Finished' section again, this time with correct 'Submitted' and 'Grading' value, so that now the 'Finished' section contains both an invalid entry and a valid one.

[fogti]

environment: the server probably runs (on) the follwing fork: https://github.com/tuc-osg/opensubmit