[serverless-apollo-contentful] Set up message queueing

[kenslachtajr]

Description

• SQS is the answer (see how Dustin did it in his kit, should be roughly identical). It's not the event processor for DynamoDB but the endpoint that generated an example job. There's a use case here where you get a hook back from contentful on a model change and need to do some processing in the background. Set it up as something basic, but document in the README about it