chore: Disable fetching new emails after mailbox error (#4176)

- Disabled email fetch job if credentials for the channel isn't working
- notify customers when the email channel isn't working

fixes: https://github.com/chatwoot/chatwoot/issues/4174

app/models/channel/email.rb

@@ -34,6 +34,7 @@
 
 class Channel::Email < ApplicationRecord
   include Channelable
+  include Reauthorizable
 
   self.table_name = 'channel_email'
   EDITABLE_ATTRS = [:email, :imap_enabled, :imap_email, :imap_password, :imap_address, :imap_port, :imap_enable_ssl, :imap_inbox_synced_at,