Documentation of custom content filters CLI usage in Azure OpenAI

### Preconditions

- [X] No need to upgrade Python SDK or the Python SDK is ready.

### Related command

_No response_

### Resource Provider

N/A

### Description of Feature or Work Requested

Looking for clarity on how to leverage the CLI to do maintenance for the following operations:
1. Deploying and configuring a Content Filtering configuration.
2. Assigning a custom content filter to a model deployment

### Minimum API Version Required

N/A

### Swagger PR link / SDK link

N/A

### Request Example

_No response_

### Target Date

2024-01-01

### PM Contact

ellbe@microsoft.com

### Engineer Contact

shbenela@microsoft.com

### Additional context

_No response_