THRIFT-421. rb: Fix tests broken by original patch

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@762928 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/test/rb/generation/test_struct.rb b/test/rb/generation/test_struct.rb
index fbb4776..3bd4fc9 100644
--- a/test/rb/generation/test_struct.rb
+++ b/test/rb/generation/test_struct.rb
@@ -18,7 +18,7 @@
 #
 
 require File.join(File.dirname(__FILE__), '../test_helper')
-require 'SmallService'
+require 'small_service'
 
 class TestStructGeneration < Test::Unit::TestCase