Upgrading XWiki fails to upgrade mandatory xclass definitions

Seems that XWIKI-13971 caused this regression in commit https://github.com/xwiki/xwiki-platform/commit/f9d61d726f898ee80c67c250c0db491a7fe5b427

Before the commit we were using "needsUpdate" to check for changes in the xclass xproperties and those were removed in the refactoring apparently...