Why doesn’t SessionDataSet implement the IAsyncDisposable interface?

Currently, SessionDataSet implements the IDisposable interface. However, in its Dispose() method, the asynchronous Close() method is invoked synchronously.

Actual implementation:
```csharp
protected virtual void Dispose(bool disposing)
{
if (this.disposedValue)
return;
if (disposing)
{
try
{
//synchronous call
this.Close().Wait();
}
catch
{
}
}
this.disposedValue = true;
}
```

Proposed implementation:
```csharp
protected virtual Task DisposeAsync(bool disposing)
{
if (this.disposedValue)
return;
if (disposing)
{
try
{
//asynchronous call
await this.Close();
}
catch
{
}
}
this.disposedValue = true;
}
```

定位 SessionDataSet，并检查其现有的 IDisposable 实现，尤其是 Dispose() 和异步 Close() 入口点。确认该类支持异步释放，并且在不改变现有同步释放行为的情况下等待 Close() 完成；该 issue 未提供测试或文件路径，因此应针对两条释放路径检查完成情况。

由索引模型根据 Issue 内容生成。