Add command to manually refresh Heroku status in PRs (#503)

.github/workflows/heroku.yaml

@@ -1,15 +1,20 @@
-name: Heroku
 # Based on https://janjones.me/posts/github-action-heroku-deployment/
+name: Heroku
 
-on: deployment_status
+on:
+ deployment_status:
+ issue_comment:
+ types: [created, edited]
 
 jobs:
  deployment-status:
  name: Check deployment status
  runs-on: ubuntu-latest
 
- # Continue only if some definitive status has been reported.
- if: github.event.deployment_status.state != 'pending'
+ # Continue only if some definitive status has been reported. Also allow
+ # manual refresh of status checks by commenting '/refresh-heroku-status'.
+ if: ${{ github.event.deployment_status.state != 'pending'
+ || (contains(github.event.comment.body, '/refresh-heroku-status') && github.event.issue.pull_request) }}
 
  steps:
  # Forward deployment's status to the deployed commit.
@@ -29,8 +34,10 @@ jobs:
  name: Check site health
  runs-on: ubuntu-latest
 
- # Run health check only if deployment succeeds.
- if: github.event.deployment_status.state == 'success'
+ # Run health check only if deployment succeeds. Also allow manual refresh
+ # of status checks by commenting '/refresh-heroku-status'.
+ if: ${{ github.event.deployment_status.state == 'success'
+ || (contains(github.event.comment.body, '/refresh-heroku-status') && github.event.issue.pull_request) }}
 
  # Check that the deployed app returns successful HTTP response.
  steps: