VSD - Add link to VSD from the groups page

Problem

VSD is a new dashboard introduce in %16.0.

In GitLab, navigating through various pages becomes a tricky task, especially for users who are unfamiliar with the platfrom and do not have in-depth knowledge of its structure and what's new.

Proposal

Improve the approachability of VSD by providing contextual links to guide users from the general group page (e.g. https://gitlab.com/groups/gitlab-org) to VSD.

1. On the groups page add drill-down link to VSD.
2. The link will be from Recent activity counter.
3. GitLab Ultimate only.

This is similar to the drill-down links we already have today from the Merge requests created, Issues created and Members added: