add new telemetry events for features behind a SKU

source/manage/telemetry.rst

@@ -161,6 +161,10 @@ Non-personally Identifiable Diagnostic Information, distinguished by end users a
   - *System Console Menu Discovery Diagnostics:* Clicks on the hamburger menu items of the System Console, including Administrator's Guide, Troubleshooting Forum, Commercial Support, About Mattermost, and clicks on the left-hand side navigation menu items
   - *In Product Notices Diagnostics:* Notices viewed, and the notices on which an action button was clicked.
   - *Threaded discussions:* Clicks to reply to a thread, reply using the footer element, filter threads by unread, mark as read, access to global threads section.
+  - *Custom Groups:* Invite people to a channel by using a custom group, mention a custom group, and modify a custom group.
+  - *Read-Only Channels:* Navigate to a read-only channel, and post a message to a read-only channel.
+  - *Shared Workspaces:* Navigate to a shared channel, post a message in a shared channel, and mention a remote user.
+  - *Guest Accounts:* Mention a guest account, directly message a guest, and add a guest to a channel.
 
 Playbooks telemetry
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