Kubernetes Cilium egress DNS policy

I am looking to implement an egress policy using Cilium – I just need one example to work.

For example if our email microservice needs to send an email using Sendgrid, the pod should only be able to send to sendgrid.com

Here is the Cilium documentation:
https://docs.cilium.io/en/v1.8/gettingstarted/dns/