Add require_once to update.php due to routing
Add require_once to update.php due to routing

Fixes https://github.com/owncloud/core/issues/10585
Partially reverts 52d5429768acdb87b2dc2efedc89eb4ad0d29139
endsguy/server,andreas-p/nextcloud-server,michaelletzgus/nextcloud-server,sharidas/core,endsguy/server,xx621998xx/server,endsguy/server,jbicha/server,pollopolea/core,whitekiba/server,pixelipo/server,Ardinis/server,IljaN/core,sharidas/core,bluelml/core,andreas-p/nextcloud-server,owncloud/core,xx621998xx/server,IljaN/core,lrytz/core,nextcloud/server,cernbox/core,Ardinis/server,bluelml/core,phil-davis/core,michaelletzgus/nextcloud-server,owncloud/core,jbicha/server,lrytz/core,pixelipo/server,lrytz/core,owncloud/core,pmattern/server,bluelml/core,pmattern/server,bluelml/core,IljaN/core,nextcloud/server,endsguy/server,bluelml/core,lrytz/core,pollopolea/core,Ardinis/server,xx621998xx/server,owncloud/core,pixelipo/server,whitekiba/server,andreas-p/nextcloud-server,pmattern/server,pixelipo/server,whitekiba/server,cernbox/core,sharidas/core,jbicha/server,cernbox/core,endsguy/server,andreas-p/nextcloud-server,Ardinis/server,nextcloud/server,cernbox/core,pixelipo/server,andreas-p/nextcloud-server,whitekiba/server,pollopolea/core,pollopolea/core,sharidas/core,sharidas/core,jbicha/server,xx621998xx/server,michaelletzgus/nextcloud-server,pmattern/server,IljaN/core,lrytz/core,IljaN/core,pollopolea/core,nextcloud/server,xx621998xx/server,whitekiba/server,michaelletzgus/nextcloud-server,pmattern/server,owncloud/core,Ardinis/server,cernbox/core,jbicha/server