minor #19100 [Messenger] Add mention of workers restarting with supervisor (alexandre-daubois)

This PR was merged into the 5.4 branch.

Discussion
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[Messenger] Add mention of workers restarting with `supervisor`

I think it may be a good thing to add this little line, so people doesn't think that calling `supervisorctl start` will update the worker code or whatsoever. I just came across a project where this confusion was made 🙂

Commits
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186885e [Messenger] Add mention of workers restarting with `supervisor`

Author: OskarStark

messenger.rst

@@ -726,6 +726,10 @@ Next, tell Supervisor to read your config and start your workers:
 
     $ sudo supervisorctl start messenger-consume:*
 
+    # If you deploy an update of your code, don't forget to restart your workers
+    # to run the new code
+    $ sudo supervisorctl restart messenger-consume:*
+
 See the `Supervisor docs`_ for more details.
 
 Graceful Shutdown