[DevOps Adoption] Show total number of features adopted

Overview

As a business leader, I want a quick way to understand how many GitLab features have been adopted by my teams so I can

1. See how much value we are getting out of GitLab and justify renewing our GitLab contract
2. Evaluate the state of our DevOps transformation
3. Evaluate progress on moving to GitLab so that we can reduce the number of tools in our DevOps toolchain

Proposal

Add an overview section to the DevOps Adoption page that shows the number of features adopted out of the total number of features that are tracked in the adoption table.

Requirements

• Add an Overview section at the top of the DevOps Adoption page above the adoption table. The Overview section has the following four horizontal sections as shown in the attached design:
  1. Overall Adoption
  2. Dev
  3. Sec
  4. Ops
• Each section has an icon next to the name as shown in the design
• Under the title of each section is text showing the number of features adopted out of the total number of features that we're tracking for that section. For example, under Dev "3/4 key features adopted"
• Overall Adoption is an aggregation of Dev, Sec, and Ops
• To calculate the number of features adopted, we check the features adopted in the current group and any sub groups that appear in the adoption table.
• Update the UI text at the top of the page to read "Feature adoption is based on usage in this group and its sub groups over the last 30 days. Last updated ..."

Note Exact string TBD based on #329708 (closed) and pending TW review

• Include a progress bar for Overall adoption, Dev, Sec, and Ops using the following colours:
  • Dev - dv-orange-600
  • Sec - dv-aqua-500
  • Ops - dv-green-600
• Add to both the instance level and group level feature
• Add supporting user documentation describing the value of the overview section and how it works
• Release post (announce #326480 (comment 572149641) at the same time)

Out of scope

• Do not include a percentage. We will add a percentage later when we have more features available in the adoption table. Otherwise users may be confused why their percentage continues to change every time we add an additional feature to the table.
• Do not include tier information for each feature. We will do that in a future iteration.