Require mediawiki::multiverison in ::mediawiki contexts

Attempt to ensure that the configuration scripts created by
mediawiki::multiverison are in place before any attempted execution of
MediaWiki code by requiring mediawiki::multiverison in contexts where
exec will be run.

Bug: 69816
Change-Id: I5b8d8516bfe6ba216fae219663c72a4ff8e265be