References to Azure DDoS Standard plan should be changed to Azure DDoS Network Plan

### Community Note

- Please vote on this issue by adding a 👍 [reaction](https://blog.github.com/2016-03-10-add-reactions-to-pull-requests-issues-and-comments/) to the original issue to help the community and maintainers prioritize this request
- Please do not leave "+1" or "me too" comments, they generate extra noise for issue followers and do not help prioritize the request
- If you are interested in working on this issue or have submitted a pull request, please leave a comment

### Versions

N/A

### Description

Documentation references Azure DDoS Standard, which has been replaced with Azure DDoS Network Protection.

#### Describe the bug

Still some references to the older Azure DDoS Standard plan in the documentation and on diagrams, these should be swapped over to the Azure DDoS Network Protection.

#### Steps to Reproduce

References seen on:
1. [[User Guide] Connectivity Resources](https://github.com/Azure/terraform-azurerm-caf-enterprise-scale/wiki/%5BUser-Guide%5D-Connectivity-Resources):

> The module can also create and link [DDoS Protection](https://github.com/Azure/terraform-azurerm-caf-enterprise-scale/wiki/%5BUser-Guide%5D-Connectivity-Resources#ddos-protection-plan) **Standard** to Virtual Networks, and manage centralized public and private [DNS zones](https://github.com/Azure/terraform-azurerm-caf-enterprise-scale/wiki/%5BUser-Guide%5D-Connectivity-Resources#dns).

2. In the [ALZ overview](https://raw.githubusercontent.com/wiki/Azure/terraform-azurerm-caf-enterprise-scale/media/alz-tf-module-overview.png) diagram
3. In the [connectivity](https://github.com/Azure/terraform-azurerm-caf-enterprise-scale/wiki/media/terraform-caf-enterprise-scale-connectivity.png) diagram
4. In the [virtual wan](https://github.com/Azure/terraform-azurerm-caf-enterprise-scale/wiki/media/terraform-caf-enterprise-scale-virtual-wan.png) diagram

Might be others. I note that the [Enterprise Scale Architecture](https://github.com/microsoft/CloudAdoptionFramework/raw/main/ready/enterprise-scale-architecture.vsdx) Visio diagram that these diagrams are based on has been updated, and that @jtracey93 updated the [ns-arch-cust-expanded.svg](https://github.com/MicrosoftDocs/cloud-adoption-framework/blob/main/docs/ready/enterprise-scale/media/ns-arch-cust-expanded.svg) diagram on the Microsoft CAF ES doc pages last month.

#### Screenshots

#### Additional context

Start with the linked Connectivity Resources wiki page and inspect the ALZ overview, connectivity, and virtual wan diagrams for the outdated Azure DDoS Standard wording. Search the documentation and diagrams for other occurrences, then verify that all references use Azure DDoS Network Protection and match the updated CAF terminology.

Written by the indexing model from the issue text.