test_signal.rb: missing argv

* test/ruby/test_signal.rb (test_hup_me): add missing argv.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45893 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_signal.rb

@@ -256,7 +256,7 @@ EOS
     # that signal will be deliverd synchronously.
     # This ugly workaround was introduced to don't break
     # compatibility against silly example codes.
-    assert_separately(<<-RUBY)
+    assert_separately([], <<-RUBY)
     trap(:HUP, "DEFAULT")
     assert_raise(SignalException) {
       Process.kill('HUP', Process.pid)