Reorganize content on issue pagees
Problem to solve
Due to information being spread across the following three pages, it is difficult to simply follow instructions to create a new issue in the UI and understand the display of Similar Issues in the process.
In the Create New Issue page, we should differentiate between ways to create an issue vs ways to access the New Issue UI.
https://docs.gitlab.com/ee/user/project/issues/issue_data_and_actions.html
https://docs.gitlab.com/ee/user/project/issues/create_new_issue.html
https://docs.gitlab.com/ee/user/project/issues/similar_issues.html