RCS1220 Use pattern matching instead of is+as?

An is+cast operator gets flagged by RCS1220. Should is+as also be flagged to be replaced by pattern matching?

```csharp
void Method(Control control)
{
//is+cast operator
if (control is TextBox)
{
TextBox textbox = (TextBox)control;
}

//is+as
if (control is TextBox)
{
TextBox textbox = control as TextBox;
}
}
```