[lldb] Fix TestDataFormatterStdList regression
Since D66174 I see failures of TestDataFormatterStdList in about 50% of runs on
Fedora 30 x86_64 libstdc++. I have found out that LLDB internally expects these
RegularExpressions to be matched in their alphabetical order:
But since D66174 they are sometimes matched in reverse order. In fact it was
only some luck it worked before as there is internally
std::map<lldb::RegularExpressionSP, FormatterImpl> (FormattersContainer).
Differential Revision: https://reviews.llvm.org/D66398