chomp is removing trailing newlines.

https://github.com/awslabs/aws-fluent-plugin-kinesis/blob/master/lib/fluent/plugin/kinesis.rb#L108

Here, the additional formatting - chomp - is causing newlines to be removed that the JSON formatter is adding by default. I think at this point we should rely on the formatter and not do any post-processing. 