These tests were all using WpfFact, but not actually doing anything
that required either WPF or an STA thread. We plan to enable
parallelization of Facts (but not WpfFacts), and this ensures we can
parallelize as many tests as possible.

Moved many of the blocking waits to await in the test infrastructure.
This resolves the remaining sources of observed instability in the
tests.

Now that the comment formatting issue is fixed in the Formatter type, we can run the formatter on the remainder of the VB code base.

closes #1424