TestBasicDispatcherProvider

"Basic" TestDispatcherProvider which mimics production behavior, without the automatic time control of TestCoroutineDispatcher and without the need for Dispatchers.setMain

The default, io, and unconfined properties just delegate to their counterparts in Dispatchers.

The main and mainImmediate properties share a single dispatcher and thread as they do with the Dispatchers.setMain(...) implementation from kotlinx-coroutines-test.