Restores “recent videos” sidebar list for Satire sites (Onion and upcoming Clickhole).

Onion stream page’s “Recent Videos” sidebar stopped displaying in March 2018 when mkSidebarPost()was changed to require non-empty-string Bylines.

This “show byline” change caused the mkSidebarPost() flow to instead attempt to show Author name, but since this wasn’t resolved it silently failed, effectively filtering out all posts.

This solution seems like the best approach since mkSidebarPost() expects resolved Authors.

https://github.com/gawkermedia/kinja-mantle/pull/14244