Updating documentation to include a missing step in the update procedure
See the general Documentation guidelines http://docs.gitlab.com/ce/development/doc_styleguide.html
What does this MR do?
This MR updates an update documentation document (specifically the 8.2 -> 8.3
one) to include a missing step in the procedure, the update of the GitLab default file contents.
Moving docs to a new location?
No.