Add streaming audit events for visiting CI/CD Settings page via Project and Group view

What does this MR do and why?

Adding a streaming audit event for when a user visits CI/CD Settings on a Group and Project page.

References

#555959 (closed)

How to set up and validate locally

To see the event in action for PROJECT follow below steps:

1. Checkout my branch

2. Start gdk and make sure you have the Ultimate or Premium plan.

3. Go to a project under the root user (user must have Administrator access on the instance).

4. Go to Settings (last item in the left sidebar) -> CI/CD. Opening CI/CD should trigger the event already.

5. Head to rails console and run cat log/audit_json.log, look up project_ci_cd_settings_accessed, you should see a log like below:

   

To see the event in action for GROUP follow below steps:

1. Checkout my branch
2. Start gdk and make sure you have the Ultimate or Premium plan.
3. Go to a group under the root user (user must have Administrator access on the instance).
4. Go to Settings (last item in the left sidebar) -> CI/CD. Opening CI/CD should trigger the event already.
5. Head to rails console and run cat log/audit_json.log, look up group_ci_cd_settings_accessed, you should see a log like below:

---

For both Group and Project:

1. Another way to validate is to follow above steps 1 to 4.
2. Go to Admin view -> Monitoring -> Audit events (Here you should see the log that was added when you visited the above page).

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

I followed below docs while working on adding these event audit logs:

1. https://docs.gitlab.com/user/compliance/audit_events/
2. https://docs.gitlab.com/development/audit_event_guide/#how-to-instrument-new-audit-events
3. https://docs.gitlab.com/administration/compliance/audit_event_streaming/