Add per project counts for feature usage in Usage Ping

Problem

Its difficult to determine both feature usage and stage adoption without greater granularity at the project/group level. For example...

• In determining Plan stage usage/adoption, we need to know how many projects are using GitLab issues.
• In determining Verify stage usage/adoption, we need to know how many projects have .gitlab-ci.yml file and/or a green pipeline.
• In determining Secure stage usage/adoption, we need to know how many projects have run one of our security tests.
• etc.

And we should not simply divide the total count of these objects by the number of projects... that's an average and not an accurate count of feature use.

Proposal

Start counting how many projects are specifically using these features.

Result

This will give us an accurate count of projects using feature which helps us determine stage adoption and accurate feature usage.