Audit log git events API in GHES and GHAE

[github-product-roadmap]

Summary

Following on from the addition of the complete REST API for audit log events in GHES and GHAE in 3.3 in #216, we will ship git events APIs to GHAE and GHES in 3.5. This brings parity with the REST API capabilities in GHEC.

We will launch this feature with a configurable retention period for git events so that there is a limited and reasonable additional impact on GHES storage infrastructure by default.

Intended Outcome

The goal is to provide customers with the ability to consume git events in the audit log alongside all other audit log data via the REST APIs.

How will it work?

We will ship the API with a similar schema to GHEC. We will implement a default storage retention period for git events. For GHES, the retention period will be configurable by enterprise owners in the compliance tab of the enterprise overview.

[spaltrowitz]

this has shipped to GHES! https://docs.github.com/enterprise-server@3.5/admin/release-notes#git-events-in-the-enterprise-audit-log

leaving open to track to GHAE 3.5