Handle sending mail more properly

With custom sentry reporting issues

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/web/email/follow.ex

@@ -62,7 +62,7 @@ defmodule Mobilizon.Web.Email.Follow do
     |> assign(:follower, follower)
     |> assign(:subject, subject)
     |> render(:instance_follow)
-    |> Email.Mailer.deliver_later()
+    |> Email.Mailer.send_email_later()
 
     :ok
   end