test_env.rb: escape

* test/ruby/test_env.rb (TestEnv#test_utf8): escape non-ASCII
  string with \u explicitly.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52901 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_env.rb

@@ -485,7 +485,7 @@ class TestEnv < Test::Unit::TestCase
 
     if Encoding.find("locale") == Encoding::UTF_8
       def test_utf8
-        text = "testing åáâäãāあ"
+        text = "testing \u{e5 e1 e2 e4 e3 101 3042}"
         test = ENV["test"]
         ENV["test"] = text
         assert_equal text, ENV["test"]