Remove extra assertion.

This is really testing the library. And it breaks the build
on 1.8.7.

Author: steveklabnik

test/resque_failure_redis_test.rb

@@ -1,13 +1,6 @@
 require 'test_helper'
 require 'resque/failure/redis'
 
-unless defined?(JSON)
-  module JSON
-    class GeneratorError
-    end
-  end
-end
-
 context "Resque::Failure::Redis" do
   setup do
     @bad_string    = [39, 250, 141, 168, 138, 191, 52, 211, 159, 86, 93, 95, 39].map { |c| c.chr }.join
@@ -20,10 +13,6 @@ class GeneratorError
 
   test 'cleans up bad strings before saving the failure, in order to prevent errors on the resque UI' do
     # test assumption: the bad string should not be able to round trip though JSON
-    assert_raises(MultiJson::DecodeError, JSON::GeneratorError) {
-      MultiJson.decode(MultiJson.encode(@bad_string))
-    }
-
     @redis_backend.save
     Resque::Failure::Redis.all # should not raise an error
   end