fixes registering of theming settings where server return OC_Defaults instead of ThemingDefaults
fixes registering of theming settings where server return OC_Defaults instead of ThemingDefaults

xx621998xx/server,pmattern/server,Ardinis/server,xx621998xx/server,michaelletzgus/nextcloud-server,xx621998xx/server,Ardinis/server,pmattern/server,endsguy/server,pixelipo/server,pixelipo/server,jbicha/server,whitekiba/server,nextcloud/server,andreas-p/nextcloud-server,michaelletzgus/nextcloud-server,pmattern/server,endsguy/server,pixelipo/server,nextcloud/server,endsguy/server,Ardinis/server,whitekiba/server,michaelletzgus/nextcloud-server,jbicha/server,xx621998xx/server,pixelipo/server,whitekiba/server,andreas-p/nextcloud-server,pmattern/server,jbicha/server,whitekiba/server,xx621998xx/server,nextcloud/server,jbicha/server,Ardinis/server,nextcloud/server,endsguy/server,andreas-p/nextcloud-server,Ardinis/server,andreas-p/nextcloud-server,endsguy/server,michaelletzgus/nextcloud-server,whitekiba/server,pixelipo/server,pmattern/server,andreas-p/nextcloud-server,jbicha/server