Failing test: verify_message/1

[mbklein]

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Environment

• Elixir 1.9.0 (compiled with Erlang/OTP 20)
• Erlang/OTP 21 [erts-10.3] [source] [64-bit] [smp:4:4] [ds:4:4:10] [async-threads:1] [hipe]
• ExAws 2.1.1
• Hackney 1.15.2

Current behavior

I'm trying to submit a PR to provide a new :get_subscription_attributes parser that properly handles FilterPolicy and other attributes not currently implemented. In running the test suite, test verify_message/1 fails due to a cert PEM file that cannot be retrieved (likely because it has expired and been replaced by a new PEM).

  1) test verify_message/1 validate a pristine message from SNS (ExAws.SNSTest)
     test/lib/sns_test.exs:279
     Assertion with == failed
     code:  assert :ok == SNS.verify_message(message)
     left:  :ok
     right: {:error,
             "Could not fetch certificate from https://sns.eu-west-1.amazonaws.com/SimpleNotificationService-b95095beb82e8f6a046b3aafc7f4149a.pem, expected http code 200, got: 404"}
     stacktrace:
       test/lib/sns_test.exs:280: (test)

Expected behavior

Test suite passes