Updated mediawiki/extensions
Project: mediawiki/extensions/Flow  51cda2b0c105b1e51c10550e29227abc21904a11

Get rid of ApiQueryFlow

* It's been deprecated for awhile.
* We pretty much ignore it, so could be broken any time
* Pretty sure we didn't even have consumers yet

Change-Id: I871cc6cfbadb99397a155044cadd23d1e944f204