Updated mediawiki/extensions
Project: mediawiki/extensions/Flow  50fdff82aa3bfccc4751f10b33c1d38c052c6a85

Utilize LinkBatch for gender, NS_USER, and NS_USER_TALK lookups

Also split the query method out of UserNameBatch to simplify writing
the tests.

Change-Id: I55932951a90ea2295a3918f7b45490c4122c2770