remove patch for db cleaner (version bump seemed to resolve it)

features/support/database_cleaner_patches.rb

@@ -22,15 +22,3 @@ module ActiveRecord
   end
 end
 
-DatabaseCleaner::ActiveRecord::Truncation.class_eval do
-  # You could argue that this technically isn't truncation. You'd be right.
-  # But something in the MySQL adapter segfaults (!) on actual truncation, and we
-  # don't have that much data in our tests, so a DELETE is not appreciably slower.
-  def clean
-    connection.disable_referential_integrity do
-      tables_to_truncate.each do |table_name|
-        connection.execute("DELETE FROM #{table_name};")
-      end
-    end
-  end
-end