[docs] update docs re: removing old instances when switching editions
Some feedback via Slack:
Some minor feedback points on https://docs.rhodecode.com/RhodeCode-Control/tasks/switch-editions.html ...
- Works great! Auto-upgrade on the linked page is magic
- It's not clear for a n00b like me how to remove the old instance
- Because the old instance isn't stopped during the switch, another port has to be selected with the proxying webserver reconfigured. There might be a way to do this better then?