Merge branch 'doc-update-mail-room-development' into 'master'

Add more detail about mail_room version update for local development

See merge request gitlab-org/gitlab!80036

doc/development/emails.md

@@ -89,6 +89,8 @@ See the [Rails guides](https://guides.rubyonrails.org/action_mailer_basics.html#
 
    As mentioned, the part after `+` is ignored, and this message is sent to the mailbox for `gitlab-incoming@gmail.com`.
 
+1. Read the [MailRoom Gem updates](#mailroom-gem-updates) section for more details before you proceed to make sure you have the right version of MailRoom installed. In summary, you need to update the `gitlab-mail_room` version in the `Gemfile` to the latest `gitlab-mail_room` temporarily and run `bundle install`. **Do not commit** this change as it's a temporary workaround.
+
 1. Run this command in the GitLab root directory to launch `mail_room`:
 
    ```shell