Track number of project that enabled Validity Checks

What does this MR do and why?

Track number of project that enabled Validity Checks

Changelog: added EE: true

References

Telemetry - track validity checks usage (#519785 - closed)

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Run rspec test
2. In rails console run Gitlab::Usage::ServicePingReport.for(output: :all_metrics_valu es)['counts']['projects_with_validity_checks_enabled'] which will output a bunch but at the very end should display how many projects in your gdk have validity checks on

MR acceptance checklist

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