Updated mediawiki/extensions
Project: mediawiki/extensions/Wikibase  a891a16cbc89f50eac135b16e1d05afb0a79c5e4

Fix NamespaceChecker

Fix edge cases in namespace checker and provide test cases.

Change-Id: I3eeaec158f5a91bd6dadadc833f92b15a0dbe41e