Add Support for ConfigureAwaitOptions in .NET 8

[brminnick]

This PR adds support for ConfigureAwaitOptions in .NET 8.0+

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.NET 8.0 Introduces ConfigureAwaitOptions that allow users to customize the behavior when awaiting:

• ConfigureAwaitOptions.None
  • No options specified
• ConfigureAwaitOptions.SuppressThrowing
  • Avoids throwing an exception at the completion of awaiting a Task that ends in the Faulted or Canceled state
• ConfigureAwaitOptions.ContinueOnCapturedContext
  • Attempts to marshal the continuation back to the original SynchronizationContext or TaskScheduler present on the originating thread at the time of the await
• ConfigureAwaitOptions.ForceYielding
  • Forces an await on an already completed Task to behave as if the Task wasn't yet completed, such that the current asynchronous method will be forced to yield its execution

For more information, check out Stephen Cleary's blog post, "ConfigureAwait in .NET 8".