Testing - Check Dispose call timing for OutOfProcess tests

From @eeaston:

> Running the dispose method when using OutOfProcess mode throws errors due to I think closed process handles.
>
> // Clean-up for the class is in the IDisposable.Dispose implementation
> public void Dispose()
> {
> wb.Close(SaveChanges: false);
> }
>

No file or test path is named. Start by locating the OutOfProcess tests and the IDisposable.Dispose implementation shown in the report, then reproduce the failure around wb.Close(SaveChanges: false). Done means the disposal timing no longer raises closed-process-handle errors and the behavior is covered by a test.

Written by the indexing model from the issue text.