fix malformed verification link sent in mails

internal/mailing/mailtemplates/templates/verify_mail.html.mustache

@@ -2,7 +2,7 @@ Your email address was entered to be used for mytoken notifications at <a href="
 You must verify that this email address belongs to you. Please verify by clicking on the following link or copy it to
 the address bar of your browser:
 
-<a href="{{link}}">{{ link }}</a>
+<a href="{{{link}}}">{{{ link }}}</a>
 
 Sincerly,
 the mytoken mail sender bot.

internal/mailing/mailtemplates/templates/verify_mail.txt.mustache

@@ -2,7 +2,7 @@ Your email address was entered to be used for mytoken notifications at {{ issuer
 You must verify that this email address belongs to you. Please verify by clicking on the following link or copy it to
 the address bar of your browser:
 
-{{ link }}
+{{{ link }}}
 
 Sincerly,
 the mytoken mail sender bot.
\ No newline at end of file