cloudwatch_lambda.js uses old, deprecated `context` object about sumologic-aws-lambda

[himanshu219]

Yes agree and we use callback() in our new version of cloudwatch lambda function (dlq_processor). @duchatran do we want to maintain backward compatibility with old nodejs versions? Otherwise I can migrate this one to async await which will save us from callback hell.

[blimmer]

The setup docs state that you should select the Node 8 runtime when you set up the lambda:

https://github.com/SumoLogic/sumologic-aws-lambda/blob/22a1dcb518ee53b2cbf66e4d17ba010e76a22081/cloudwatchlogs/README.md#create-lambda-function

So I think it'd probably be fair to drop the backwards compatibility. Additionally, Node 4 has been deprecated on the lambda side so I'd assume folks will upgrade to the latest runtime when updating their lambdas.