Add workers settings to configuration manual (#14086)

* Add workers settings to configuration manual
* Update `pusher_instances`
* update url to python logger
* update headlines
* update links after headline change
* remove link from `daemon process`

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* extend example for `federation_sender_instances` and `pusher_instances`
* more infos about stream writers
* add link to DAG
* update `pusher_instances`
* update `worker_listeners`
* update `stream_writers`
* Update `worker_name`

Co-authored-by: David Robertson <davidr@element.io>