Make clear that it are database migrations

CONTRIBUTING.md

@@ -160,8 +160,8 @@ If you add a dependency in GitLab (such as an operating system package) please c
 1.  [CoffeeScript](https://github.com/thoughtbot/guides/tree/master/style#coffeescript)
 1.  [Shell commands](doc/development/shell_commands.md) created by GitLab contributors to enhance security
 1.  [Markdown](http://www.cirosantilli.com/markdown-styleguide)
+1.  [Database Migrations](doc/development/migration_style_guide.md)
 1.  Interface text should be written subjectively instead of objectively. It should be the gitlab core team addressing a person. It should be written in present time and never use past tense (has been/was). For example instead of "prohibited this user from being saved due to the following errors:" the text should be "sorry, we could not create your account because:". Also these [excellent writing guidelines](https://github.com/NARKOZ/guides#writing).
-1. [Migrations](doc/development/migration_style_guide.md)
 
 This is also the style used by linting tools such as [RuboCop](https://github.com/bbatsov/rubocop), [PullReview](https://www.pullreview.com/) and [Hound CI](https://houndci.com).
 
@@ -177,4 +177,4 @@ Project maintainers have the right and responsibility to remove, edit, or reject
 Instances of abusive, harassing, or otherwise unacceptable behavior can be
 reported by emailing contact@gitlab.com
 
-This Code of Conduct is adapted from the [Contributor Covenant](http:contributor-covenant.org), version 1.0.0, available at [http://contributor-covenant.org/version/1/0/0/](http://contributor-covenant.org/version/1/0/0/)
+This Code of Conduct is adapted from the [Contributor Covenant](http:contributor-covenant.org), version 1.0.0, available at [http://contributor-covenant.org/version/1/0/0/](http://contributor-covenant.org/version/1/0/0/)
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