The `AnyError` placeholder error can cause tests to succeed for errors
other than what was expected. That is, the use of `AnyError` can mask
bugs in a unit test. So replace it with the specific error, or error type,
the test expects to be raised.
This does not remove the anyError structure because it is used in
the TestCase.DoesNotCompile() method. To keep the size of this change
as small as possible I want to defer updating that use to a separate
change. However, remove the public AnyError var so future test writers
don't attempt to use it.
I was surprised to see so many legacy lambda syntax examples in the
documentation. This replaces all of them with the new syntax -- excluding
the handful of cases meant to explicitly verify the legacy form is still
valid. This also adds a link to the issue in the release notes which
documents the change in syntax.
Related #664
