Incoherent whitelist behaviour?

[BigFlagBurito]

Describe the bug
When testing the new whitelist function, I noticed two things.

1. if you want to edit a submission and download the submission there, the whitelist is ignored and all files are downloaded.
2. if the notebook extension *.ipynb is specified in the whitelist, notebooks from the students are ignored. Only the files created by the instructor will be downloaded.

I am not sure if this is how it should be or if it is a bug?

[florian-jaeger]

1. Currently the whitelist feature is only implemented for whitelisting autograded submission outputs, but the original idea was also to only push whitelisted files during the creation of a submission. Hopefully, at some point in the coming months we can finish the implementation.
2. This seems to be a bug and we will look into it.