Replace deprecated mw.util.wikiGetlink by mw.util.getUrl

Simplify URL generation by using mw.util.getUrl instead of the mw.Uri.

mw.Uri is buggy because it does not support IPv6 URIs (bug 64884).

Bug: 64886
Change-Id: Icf87f3ce7a8e046d34629594cce4d75e6936bf25