Updated mediawiki/extensions
Project: mediawiki/extensions/Wikibase  ef69e4d7b81dc66d7da46cbb68bced25ed201ed8

Properly validate site ids in SpecialSetSiteLink

Using SiteLinkTargetProvider which the api also uses.

To prevent things like:
https://www.wikidata.org/w/index.php?diff=181731621

Change-Id: Iec23f779382dc8b719d8c82d89377f4663801255