Remove warnings about redefined methods from Activesupport tests

when running the activesupport tests, you get the following errors:

test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_fish
test/inflector_test.rb:54: warning: previous definition of test_pluralize_fish was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_jeans
test/inflector_test.rb:54: warning: previous definition of test_pluralize_jeans was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_funky jeans
test/inflector_test.rb:54: warning: previous definition of test_pluralize_funky jeans was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_old_news
test/inflector_test.rb:54: warning: previous definition of test_pluralize_old_news was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_news
test/inflector_test.rb:54: warning: previous definition of test_pluralize_news was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_series
test/inflector_test.rb:54: warning: previous definition of test_pluralize_series was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_species
test/inflector_test.rb:54: warning: previous definition of test_pluralize_species was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_information
test/inflector_test.rb:54: warning: previous definition of test_pluralize_information was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_equipment
test/inflector_test.rb:54: warning: previous definition of test_pluralize_equipment was here
test/inflector_test.rb:68: warning: method redefined; discarding old test_pluralize_rice
test/inflector_test.rb:54: warning: previous definition of test_pluralize_rice was here

This patch stops you getting them. Yay!