Result summarizer may produce broken details link

[matthew-frank]

When producing the final results table for v2.1, Eric Han discovered that many of the "details" links were broken.

I believe the problem is that we try to rederive the base name of the .json file from the "pretty name" in the system_name field of the system_desc when we call _linkable_system_name() from line 51 of _details_url() rather than passing through the (non-pretty) system name we've already got on line 454.