feat: add audit log packaging

[bzarboni1]

ISSUE

[#79] - [Feature] Package and send GitHub audit log to a SIEM

The Government of Canada uses SIEM (Security Information and Event Management) technology to analyze audit logs. We need to ensure that the GitHub audit logs can be packaged up, in a well-understood format, for consumption in SIEM tooling.

---

CHANGES

This PR adds:

• A COMPLIANCE.md file outlining all of the compliance features of the toolkit, and how they relate to GH settings and ITSG-33 controls
• An action to grab audit logs for all managed organizations, for the previous day
• A refactoring of a previous action, to extract common python code

---