[semver:minor] Expose an env variable that fails the workflow instead of cancel

[moekify]

Is your feature request related to a problem? Please describe. I want to send a notification to slack whenever the orb cancels a workflow. However, currently it is not possible that the slack notifier works on cancel. There seems to be a difference between cancel and fail

Describe the solution you'd like With the use of a parameter in the command allow to fail the workflow instead of cancel.

Describe alternatives you've considered Get circleci to expose a on_cancel event.

[eddiewebb]

Love this.

[eddiewebb]

@pguinard-public-com fixed this in #115 !

3.1.x +