truncate values that are too big

[kzidane]

check50 should probably enforce some limits on the size of values in the JSON output that we don't control (and in any output format more generally). Not sure how useful it is to have 20+ MB of output.

[bxngyn]

Thanks for your comment! The new truncation logic (#359), once deployed, should solve this issue, as it prevents data that is too large from making it into the JSON output. We saw this issue with the DESE pset, where if the student's query produced a result that was too large, check50 would just crash all together if ran remotely. I can't 100% confirm that the new truncation logic fixes this crash since it's not officially deployed yet and I can only test it locally, but check50's JSON file is significantly shorter with this new framework which leads me to believe this will fix it once deployed.