Sort output to fix random breakage in the test suite.

The results that we get back from DNS are returned in an arbitrary
order. Technically that's fine, because all we want to see is the
set-difference between the actual/expected results. However, it breaks
our test suite which needs to know what certain examples will
output. This commit sorts the results, so that the output is a little
bit more deterministic (subject to network issues and changes).