CDN Endpoint: schema `DeliveryRuleUrlFileExtensionCondition.parameter` doesn't match it in response for sku `Standard_Verizon` or `Standard_Akamai`

The schema model [`DeliveryRuleUrlFileExtensionCondition.parameter`](https://github.com/Azure/azure-rest-api-specs/blob/1b04f5fce19cd330dcc0eec11a98e499c0cda50d/specification/cdn/resource-manager/Microsoft.Cdn/stable/2020-04-15/cdn.json#L2975) doesn't match it in response for sku `Standard_Verizon` or `Standard_Akamai`, as shown below:

```json
"parameters": {
"@odata.type": "#Microsoft.Azure.Cdn.Models.DeliveryRuleUrlFileExtensionConditionParameters",
"extensions": [
"jpg"
]
}
```

This blocks the implementation of the `delivery_rule` in Terraform `azurerm_cdn_endpoint` for profile skus mentioned above.

## related reference

- terraform-providers/terraform-provider-azurerm#8511

Open specification/cdn/resource-manager/Microsoft.Cdn/stable/2020-04-15/cdn.json at the DeliveryRuleUrlFileExtensionCondition.parameter definition around line 2975, then compare it with the response example for Standard_Verizon and Standard_Akamai. Done means the schema represents the shown parameters object and extensions array so the CDN delivery_rule response is accurately described.

Written by the indexing model from the issue text.