[test] more tests for UserController::setMailAddress
[test] more tests for UserController::setMailAddress

* fixes #12885

cernbox/core,endsguy/server,Ardinis/server,bluelml/core,nextcloud/server,nextcloud/server,IljaN/core,andreas-p/nextcloud-server,bluelml/core,xx621998xx/server,pollopolea/core,xx621998xx/server,Ardinis/server,whitekiba/server,andreas-p/nextcloud-server,IljaN/core,owncloud/core,pollopolea/core,pollopolea/core,owncloud/core,cernbox/core,xx621998xx/server,whitekiba/server,pollopolea/core,sharidas/core,bluelml/core,IljaN/core,lrytz/core,pmattern/server,phil-davis/core,endsguy/server,sharidas/core,owncloud/core,pmattern/server,pollopolea/core,nextcloud/server,jbicha/server,owncloud/core,xx621998xx/server,pmattern/server,IljaN/core,pmattern/server,owncloud/core,whitekiba/server,IljaN/core,whitekiba/server,endsguy/server,Ardinis/server,lrytz/core,jbicha/server,cernbox/core,lrytz/core,bluelml/core,michaelletzgus/nextcloud-server,cernbox/core,sharidas/core,whitekiba/server,michaelletzgus/nextcloud-server,michaelletzgus/nextcloud-server,jbicha/server,pixelipo/server,Ardinis/server,Ardinis/server,sharidas/core,pixelipo/server,pixelipo/server,andreas-p/nextcloud-server,endsguy/server,pmattern/server,andreas-p/nextcloud-server,pixelipo/server,lrytz/core,jbicha/server,pixelipo/server,andreas-p/nextcloud-server,michaelletzgus/nextcloud-server,bluelml/core,xx621998xx/server,sharidas/core,lrytz/core,endsguy/server,nextcloud/server,jbicha/server,cernbox/core