Merge branch 'docs/fix-releases-link' into 'master'

Fix link to blog posts in docs

See merge request gitlab-org/gitlab-ce!21820

doc/policy/maintenance.md

@@ -44,7 +44,7 @@ This decision is made on a case-by-case basis.
 ## Upgrade recommendations
-We encourage everyone to run the [latest stable release](https://about.gitlab.com/blog/categories/release/) to ensure that you can
+We encourage everyone to run the [latest stable release](https://about.gitlab.com/blog/categories/releases/) to ensure that you can
 easily upgrade to the most secure and feature-rich GitLab experience. In order
 to make sure you can easily run the most recent stable release, we are working
 hard to keep the update process simple and reliable.