`NGINX.NGINXPLUS/stable/2022-08-01` - define SKU names as Enum

Can the name of nginx deployments SKU defined as Enum values, so it can be generated in SDK and easy to use?

related swagger: https://github.com/Azure/azure-rest-api-specs/blob/1d9c9c68844d2b5883621069d5bf0c958841782f/specification/nginx/resource-manager/NGINX.NGINXPLUS/stable/2022-08-01/swagger.json#L1059

Open the related NGINX swagger.json at the referenced line and inspect how the deployment SKU name is currently defined, along with nearby enum definitions. Add the SKU names as enum values so SDK generation can expose them, then run the repository's specification validation or generation checks to confirm the schema is accepted.

Written by the indexing model from the issue text.