Add human-readable markdown summary of executed plan

[flaksp]

Today GitHub added ability to attach markdown summaries to executed steps in GitHub Actions. It would be nice to have human-readable summaries of executed plans in GitHub UI.

Resources:

• Announcement post: GitHub Actions: Enhance your actions with job summaries
• Details and examples: Supercharging GitHub Actions with Job Summaries

p.s. Not sure is this repository the best place to suggest this.

[jpogran]

This is the right place to ask. We'll have to investigate how to use this new GitHub feature with this action.

[DPatrickBoyd]

+1 for this feature!