DebugInfo: Update test case due to dumper improvements in r195698

The dumper was only dumping one pubtypes set and it was /always/ dumping
one pubtypes set even when there were zero sets. Now that the dumper
correctly dumps zero, one, or many sets, we can update this test case to
test for the absolute absence of a set rather than a bogus/accidental
zero-valued set.

llvm-svn: 195706