InstanceExport has encoding issues, is invalid json for some parsers
Summary
For those two instances:
https://grady.informatik.uni-goettingen.de/ckurs-block-inf/wise1819 https://grady.informatik.uni-goettingen.de/ckurs-block/wise1819
exporting the instance data and trying to parse it will result in an error due to weird characters in the compiler output for the compile tests.
One of the possible explanations is that the Response character encoding is not set properly.
Steps to reproduce
Go to one of the instances and export the instance data and load it into https://jsonlint.com
Example Project
What is the current bug behavior?
The returned json is invalid. It contains dubious characters.
What is the expected correct behavior?
Valid json is returned.
Relevant logs and/or screenshots
jsonlint link with failing excerpt