FEATURE REQUEST: Dry-run flag

[eitah]

Dear Cogito maintainers, Any chance you'd add a dry run configuration to your pipeline? The idea there is if a pipeline fails rather than alerting as it would do in the staging env, the pipeline step might no-op and alert the user that no request had gone out. We'd love such a feature for our staging concourse environment. I'd PR if you're open to it, or accept suggested implementations if there's something I'm not seeing in your readme. Thanks! Eli