Fix transient test failures

[bf4]

• https://ci.appveyor.com/project/joaomdmoura/active-model-serializers/build/49/job/pf3g0vp1otqecv42
• https://ci.appveyor.com/project/joaomdmoura/active-model-serializers/build/49/job/j0tijlxbeluf9r5e

 1) Failure:
ActionController::Serialization::ImplicitSerializerTest#test_cache_expiration_on_update [C:/projects/active-model-serializers/test/action_controller/serialization_test.rb:394]:
--- expected
+++ actual
@@ -1 +1 @@
-"{\"id\":1,\"title\":\"ZOMG a New Post\",\"body\":\"Body\",\"comments\":[{\"id\":1,\"body\":\"ZOMG A COMMENT\"}],\"blog\":{\"id\":999,\"name\":\"Custom blog\"},\"author\":{\"id\":1,\"name\":\"Joao Moura.\"}}"
+"{\"id\":1,\"title\":\"New Post\",\"body\":\"Body\",\"comments\":[{\"id\":1,\"body\":\"ZOMG A COMMENT\"}],\"blog\":{\"id\":999,\"name\":\"Custom blog\"},\"author\":{\"id\":1,\"name\":\"Joao Moura.\"}}"

ref: other race conditions #961 might be useful to look at

[beauby]

Yup, I saw that the other day as well.

[bf4]

Also

• https://ci.appveyor.com/project/joaomdmoura/active-model-serializers/build/52/job/t3erlut52i0t22j3
• https://ci.appveyor.com/project/joaomdmoura/active-model-serializers/build/52/job/fyady8yp0kn2lair

 1) Failure:
ActionController::Serialization::ImplicitSerializerTest#test_cache_expiration_on_update [C:/projects/active-model-serializers/test/action_controller/serialization_test.rb:394]:
--- expected
+++ actual
@@ -1 +1 @@
-"{\"id\":1,\"title\":\"ZOMG a New Post\",\"body\":\"Body\",\"comments\":[{\"id\":1,\"body\":\"ZOMG A COMMENT\"}],\"blog\":{\"id\":999,\"name\":\"Custom blog\"},\"author\":{\"id\":1,\"name\":\"Joao Moura.\"}}"
+"{\"id\":1,\"title\":\"New Post\",\"body\":\"Body\",\"comments\":[{\"id\":1,\"body\":\"ZOMG A COMMENT\"}],\"blog\":{\"id\":999,\"name\":\"Custom blog\"},\"author\":{\"id\":1,\"name\":\"Joao Moura.\"}}"

[joaomdmoura]

Are these failing only on appveyor?

[bf4]

So far that's the only place I've seen it :)