This is something that has been there for absolutely years, it is easy enough to change, see attached image.
As far as I'm aware, no bot it is just a signature, the link is back to avast.com.
It doesn't do anything unless you click it and in that case it basically says your visit to avast was as a result of the email signature of the avast email. Hovering over the link shows the full URL information, see attached image2 of this reference.