Updated Namespace example using TF tls provider to gen CA certs

[jlacefie]

What was changed

This PR adds an example of using Hashi's tls resource to generate a CA and pass that into the Temporal Namespace resource.

The Namespace resource example was changed which triggered a change to the docs example as well.

Why?

Two approaches to change exist:

• Add the tls resource example to the main Temporal Namespace example so doc generation updated the Namespace resource documentation to make this option visible to users (The path included in this PR)
• Add a new TF CA Namespace resource example that does not trigger the doc generation tool to add this sample to docs

Checklist

1. Closes

2. How was this tested:
   Tested locally and created a Namespace using Hashi's tls resource

• note : when I tested locally, i used comments to hide the simple, external CA, example from Terraform so only the tls CA based Namespace was created.

3. Any docs updates needed?
   Yes - see the option chose in Why

[swgillespie]

thank you!