docs: fix dynamic url redirects permission

[techieforfun]

Summary

I'm using Terraform to configure API Token permissions, but it gives an error for the Single Redirect Write permission. After checking the output of

data "cloudflare_api_token_permission_groups" "all" {}

I found that the correct permission to use is Dynamic URL Redirects Write.

Documentation checklist

• [x ] The documentation style guide has been adhered to.