Add location hint format for server.adobdc.net

### Is there an existing issue for this?

- [x] I have searched the existing issues

### What's missing?

This page does a great job of covering how to use a location hint within the context of an edge.adobedc.net call, but we need to add additional detail for how to use location hints with the server-to-server server.adobedc.net endpoint. (https://developer.adobe.com/data-collection-apis/docs/endpoints/) for authenticated hits.

Instead of putting the location hint in the path, you use it as prefix. For example, or2.server.adobedc.net or va6.server.adobedc.net. A new paragraph on the API format section below what's there would probably be a great place for it.

Thanks!

Open the endpoints documentation page and locate the API format section referenced in the issue. Add a paragraph explaining that authenticated server-to-server requests use the location hint as a prefix for server.adobedc.net, with examples such as or2.server.adobedc.net and va6.server.adobedc.net; done means the format is clearly documented alongside the existing edge.adobedc.net guidance.

Written by the indexing model from the issue text.