Remove not supported markup

Author: clementbiron

content/community/how-to-join-mattermost.md

@@ -21,11 +21,8 @@ After successful login, they will be redirected to the Open Term Archive workspa
 
 ![Mattermost landing page interface]({{< relref "." >}}landing-page.png)
 
-::: info
 By default, the Mattermost interface may be presented in French. If this is an issue, new members and contributors can translate the content to English using your browser’s built-in translation features.
 
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 ## Profile setup
 
 Once you're all set on Mattermost, the next thing is to set up your profile. A complete profile sets you up for meaningful interactions and connections with members interested in tracking the same terms.