'<p>' . t('You have not... Upload a picture... by @link', array('@link' =>
l(t('Edit your profile'), "user/{$account->uid}/edit")) . '</p>'

or something like that will work. You want to use l() for links. And
remember to make the translation easy. If you make the link part of a
string that requires the "editing your profile" to be part of a sentence it
may be hard to translate. Better to just make the whole sentence a link
"Please edit your profile to add a picture".