Fix invalid uuids
Fix invalid uuids

Configlet previously could generate invalid uuids.

It looks as though `two-fer` and `complex-numbers` both have invalid uuids.
Insti/exercism-ruby,exercism/xruby,Insti/xruby,NeimadTL/ruby,NeimadTL/ruby,Insti/exercism-ruby,exercism/xruby,Insti/xruby,Insti/exercism-ruby,NeimadTL/ruby