Add support for `aws_emr_cluster`

[guthy2010]

Hi,

I have received the following output from the following commands:

infracost breakdown --path ${PLAN}.json --format json --out-file infracost.json
infracost comment gitlab
      --gitlab-server-url $CI_SERVER_URL
      --gitlab-token $GITLAB_TOKEN
      --path infracost.json
      --repo $CI_PROJECT_PATH
      --merge-request $CI_MERGE_REQUEST_IID
      --behavior update

∙ 1 wasn't estimated, report it in https://github.com/infracost/infracost:
  ∙ 1 x aws_emr_cluster

To spin up the EMR I am using the following module https://github.com/cloudposse/terraform-aws-emr-cluster

[aliscott]

Thanks for reporting @guthy2010. We haven't added support for EMR yet but it seems important because the costs for this can be high. I'll update this issue to be for adding support for it.

If you're interested in contributing, we'd be happy to help too.