Customer feedback | az eventgrid namespace ca-certificate | need PEM file format example

### Describe the bug

This GitHub issue is being moved from Azure DevOps UUF [337756](https://dev.azure.com/msft-skilling/Content/_workitems/edit/337756).
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## Engineering request

1. Provide an example PEM file format in the `long-summary` or a separate code block.
2. The customer also needs tips for success such as

* Remove all newlines in PEM file. In Bash run `cat ./intermediate-ca.pem | tr -d '' > ./intermediate-ca-formatted.pem`
* CA certificate name can be 3-50 characters long.
* CA certificate name can include alphanumeric, hyphen(-) and, no spaces.
* The name needs to be unique per namespace.

## Customer feedback

**Repo:**

azure-docs-cli

**Title:**
az eventgrid namespace ca-certificate | Microsoft Learn

**Verbatim:**
I am begging you with every part of my being to please provide a correct example of the file format for certificate upload. The REST response simply says that it must be valid PEM, but the API rejects standard compliant PEM with newlines and the format needs to be with newlines removed.cat ./intermediate-ca.pem | tr -d '' > ./intermediate-ca-formatted.pemGets you to the right place.

**Verbatim Id:**
96adaf05-569a-ef11-8a6a-6045bd007ef6

**Live URL:**
https://learn.microsoft.com/en-us/cli/azure/eventgrid/namespace/ca-certificate

**GitHub URL:**
https://github.com/MicrosoftDocs/azure-docs-cli/blob/live/2020-09-01-hybrid/docs-ref-autogen/eventgrid/namespace/ca-certificate.yml

**UUF Triage App Feedback URL:**
https://aka.ms/UUFTriageApp?pageviewid=91b7b4b4-546c-3a2c-b628-b26d7dcd5f48

### Related command

az eventgrid namespace ca-certificate

### Errors

the API rejects standard compliant PEM with newlines and the format needs to be with newlines removed

### Issue script & Debug output

.

### Expected behavior

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### Environment Summary

Azure CLI 2.66.0

### Additional context

_No response_