Summary: We are going to use SOPS and GCP KMS to manage secrets.

Test Plan: N/A

Reviewers: michelle, oazizi, #engineering

Reviewed By: michelle, #engineering

Differential Revision: https://phab.corp.pixielabs.ai/D1821

GitOrigin-RevId: 7918d0bc30bbdce3ccc89476b8db19f1282815d1