test/unit.rb: no verbose in worker processes

* test/lib/test/unit.rb (Test::Unit::Parallel::Worker.launch):
  disable verbose flag in worker processes, get rid of unexpected
  output within marshaled results.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55832 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/lib/test/unit.rb

@@ -177,7 +177,7 @@ module Test
 
       class Worker
         def self.launch(ruby,args=[])
-          io = IO.popen([*ruby,
+          io = IO.popen([*ruby, "-W1",
                         "#{File.dirname(__FILE__)}/unit/parallel.rb",
                         *args], "rb+")
           new(io, io.pid, :waiting)