Merge branch 'patch-8' into 'master'

doc: fix gitaly url typo

See merge request !10772

doc/administration/gitaly/index.md

 # Gitaly
-[Gitaly](https://gitlab.com/gitlab-org/gitlay) (introduced in GitLab
+[Gitaly](https://gitlab.com/gitlab-org/gitaly) (introduced in GitLab
 9.0) is a service that provides high-level RPC access to Git
 repositories. As of GitLab 9.1 it is still an optional component with
 limited scope.