Remove title from mailer layout (#23078)

app/views/layouts/mailer.html.haml

@@ -4,8 +4,6 @@
     %meta{ 'http-equiv' => 'Content-Type', 'content' => 'text/html; charset=utf-8' }/
     %meta{ name: 'viewport', content: 'width=device-width, initial-scale=1.0, shrink-to-fit=no' }
 
-    %title/
-
     = stylesheet_pack_tag 'mailer'
   %body{ dir: locale_direction }
     %table.email-table{ cellspacing: 0, cellpadding: 0 }