Live links on PyCon sponsor job postings

[ewdurbin]

PyCon sponsors add job postings through their dashboard. Sometimes the links are really ugly and long.

I'm hoping we can allow live links to individual job postings on the 2019 Job Fair page. Here is the link to 2018: https://us.pycon.org/2018/sponsors/jobs/. Here is the link to the 2019 page, but there aren't any jobs posted yet: https://us.pycon.org/2019/sponsors/jobs/

Moved from https://github.com/python/psfmemberdotorg/issues/21