Remove duplicate charts installation tools navigation item

What does this MR do and why?

To avoid having two navigation items point to the same place, which causes problems for rendering the navigation, remove one of the items. Here's what it looks like before the change:

Link to review app: http://eread-fix-duplicate-charts-installation-tools-nav-item.35.193.151.162.nip.io/charts/installation/tools.html.

Merge request acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this merge request.