Summary: There was one public page for testing client plugins, and two internal ones. Combined it into a one pager, that has tabs per target, with separate content for internal versus external (didn't combine those as the testing frameworks recommended differ)
Reviewed By: nikoant
Differential Revision: D25588058
fbshipit-source-id: afa151ec0c3a5de26142938d3d389627716f1ff7