Resolve test name conflict

There are two tests named
"is possible to apply user_agent conditions to before filters with a path"
in filters_test.rb, causing "method redefined" warnings and tests not
being run.

Rename second of these to accurately describe what it's testing

test/filter_test.rb

@@ -410,7 +410,7 @@ class AfterFilterTest < Test::Unit::TestCase
     assert ran
   end
 
-  it 'is possible to apply user_agent conditions to before filters with a path' do
+  it 'is possible to apply user_agent conditions to after filters with a path' do
     ran = false
     mock_app do
       after('/foo', :user_agent => /foo/) { ran = true }