FEATURE: Allow sending group SMTP emails with from alias (#15687)

This commit allows group SMTP emails to be sent with a
different from email address that has been set up as an
alias in the email provider. Emails from the alias will
be grouped correctly using Message-IDs in the mail client,
and replies to the alias go into the correct group inbox.

app/controllers/groups_controller.rb

@@ -713,6 +713,7 @@ class GroupsController < ApplicationController
             :imap_updated_at,
             :email_username,
             :email_password,
+            :email_from_alias,
             :primary_group,
             :visibility_level,
             :members_visibility_level,