Add tracking events to group and project pages

What does this MR do and why?

To understand if other pages get more average views from new users we want to add a structured snowplow event to the project overview page. This will help us understand if new users view this page more on average and if so then it could warrant a future experiment (outside of this issue) to test adding onboarding content to that page.

We add a new structured event to the project overview and group overview pages these pages are located at the URL path of:

• Group overview
  • gitlab.com / group-name
  • example https://gitlab.com/gitlab-org
• Project overview
  • gitlab.com / group/project-name
  • example https://gitlab.com/gitlab-org/gitlab

How to set up and validate locally

1. Login and visit project page and group page

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.

Related to https://gitlab.com/gitlab-org/gitlab/-/issues/339900