"Rerun and archive sandbox" button in AWS

[prandla]

Our fork has a feature where a specific sandbox can be reran and saved as a zip file, for easier access.

Here the first testcase was reran and archived, the "1" links to a zip file that contains the entire sandbox contents.

This allows having keep_sandboxes = false in the cms config, while still allowing debugging individual submissions. it's also much easier to access the sandbox directly from AWS, instead of having to ssh into a worker and go spelunking around the filesystem. (in our case, the workers are also in docker, which further complicates finding the right sandbox...)