Remove duplicate Puma navigation item

What does this MR do and why?

Removes duplicate entry from global navigation. Remaining entry displays as: http://eread-remove-duplicate-puma-navigation-item.35.193.151.162.nip.io/ee/administration/operations/puma.html.

The effect of having two is that the navigation jumps to the first of the entries in the navigation, even if the second of the entries was selected, which is a confusing experience.

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