Adds two more ClickHouse docs to left nav (!3615) · Merge requests · GitLab.org / GitLab Docs

Add navigation item to global navigation

Link to the merge request that introduced the new page: Add merge request analytics example to ClickHou... (gitlab!112480 - merged)
Give the MR a descriptive title.
Optional. Link to the review app showing the new page:

Now that I've merged the work for @ahegyi, let's get the new ClickHouse pages in the left nav.