The Cert Manager is used during end-to-end tests to distribute the
mutual TLS authentication certs used between the cloud-sql-proxy-operator
and the kubernetes API. This is only used during E2E tests. cert-managger is not
distributed as part of this operator.

The Makefile will download an appropriate file to this directory from
the certmanager website. This file should not be added to git.

See: https://github.com/cert-manager/cert-manager

