Remove duplicate charts deployment entries on navigation

What does this MR do and why?

The docs global navigation properly supports only having a single entry on the nav per page. Though the navigation can render more than one entry for a page, it only highlights and unfurls the first one. This leads to a situation where a users is taken away from the context they selected the entry in, and moved to another.

Here's a link to the page: http://eread-remove-duplicate-charts-deployment-nav-entry.35.193.151.162.nip.io/charts/installation/deployment.html to show the context for the remaining global nav item.

Screenshots, screen recordings, or links to review app

This is the context for the item that remains and the items that are removed:

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Configure a local GitLab Docs environment: https://gitlab.com/gitlab-org/gitlab-docs/-/blob/main/doc/setup.md.

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.