Update context switcher "View all" links

What does this MR do and why?

Updates the "View all my *" links in the context switcher to point to the /dashboard/(projects|groups) paths instead of /(projects|groups).

Screenshots or screen recordings

No visual change.

How to set up and validate locally

1. Enable the new nav:

   1. Enable the feature flag:

      echo "Feature.enable(:super_sidebar_nav)" | rails c

   2. Enable the user setting from the user dropdown:

      

MR 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 MR.

Re #406579 (closed)