Documentation issues in README

[devrandom]

• "Maubot Manager > Instances > my_gitlab_bot" does not have a "path" displayed on the page. I figured out independently that the path is "/webhooks"
• if the user does not hit "Save" on the created instance page, the gitlab hook secret will change every time the docker container is restarted. I verified that the instance exists but the config is blank in the DB in this case.