unicode_norm_gen.rb: optimize concatenation
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47813 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
unicode_norm_gen.rb: optimize concatenation
concatenation instead of runtime concatenation.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47813 b2dd03c8-39d4-4d8f-98ff-823fe69b080e