Long running operations Support

In Azure SDK/API as an example,
Long running operations are performed in the following flow?

1. A URL is returned that can be used to retrieve the result of the operation once completed.
2. The URL can be used to monitor the status of the operation, at regular intervals until it is completed.
3. Optionally a callback URL is availed that can be used to get notification once a long running operation is completed.

Technically, this looks like polling and a callback URL.

Do we have a spec on this for Graph SDKs @baywet @andrueastman @darrelmiller @ddyett @Ndiritu @samwelkanda

首先查看 issue 中的 Azure SDK/API 示例和 Graph SDK 引用，以确定是否已有关于长时间运行操作、轮询和回调 URL 的规范。完成此项需要达成一致的 Graph SDK 规范或提出范围明确的实现请求；payload 未指明任何文件或测试。