Update cert-manager to use Let's Encrypt

[aarroyoc]

I've received a mail from Let's Encrypt warning than previous versions of cert-manager are causing trouble to its servers, and that they will stop accepting requests from versions inferior to 0.8.0.

We've been working with Jetstack, the authors of cert-manager, on a
series of fixes to the client. Cert-manager sometimes falls into a
traffic pattern where it sends really excessive traffic to Let's
Encrypt's servers, continuously. To mitigate this, we plan to start
blocking all traffic from cert-manager versions less than 0.8.0 (the
current semver minor release), as of November 1, 2019. Please upgrade
all of your cert-manager instances before then.

We're sending this email because this is the contact address of your
cert-manager instance at:

XXX.XXX.XXX.XX .

Version 0.8.0 is much better but we still observe excessive traffic in
some cases. We're working with Jetstack to improve these cases. As new
versions of cert-manager are released, we will add the non-current
versions to our block list after 3 months. We strongly encourage
cert-manager users to stay up-to-date with new versions.

Also, there is an opportunity to help both Jetstack and Let's Encrypt.
Once you've upgraded, please check the logs for your cert-manager
instances from time to time. Are they making excessive requests to Let's
Encrypt (more than, say, 10 per day over multiple days)? If so, please
share details at https://github.com/jetstack/cert-manager/issues/1948 .

Thanks,
Let's Encrypt Team

We should upgrade the chart

[CGandiaga]

+1.

I am receiving the following error. I agree with @aarroyoc. We should upgrade the chart.

orders controller: Re-queuing item ... Your ACME client is too old. Please upgrade to a newer version.