Remove erroneous advice
Remove erroneous advice

Per @pfg at https://community.letsencrypt.org/t/-/21318/2:

> This is not really true anymore - account recovery via email was planned to be added at some point, but has been removed from the spec since.
stweil/letsencrypt,jsha/letsencrypt,stweil/letsencrypt,lmcro/letsencrypt,letsencrypt/letsencrypt,jsha/letsencrypt,letsencrypt/letsencrypt,lmcro/letsencrypt