[EE] Move the "Limit conflicts with EE" doc to "Automatic CE-> EE merge"
EE MR for https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15749
What does this MR do?
Change the "Limit conflicts with EE" doc to "Automatic CE-> EE merge" since the doc to avoid conflicts is actually https://docs.gitlab.com/ee/development/ee_features.html (most of the things that need to be done to avoid conflicts happen in EE).