K8s deployment secrets located and moved to Vault

Created by: ElizabethStirling

All secret values in our k8s yaml files in our infrastructure, dotcom deployment and dogfood deployment repositories are located and prepared to be loaded into Vault. Note that this only encompasses environment variables and secrets that are directly stored in these repositories, rather than k8s secrets in our deployments.

This will also let us determine how the secrets are currently consumed, which will assist in more accurately estimating the work required to get Vault up and running.