update README.md

Author: bertiethorpe

README.md

@@ -147,12 +147,14 @@ Please see the [monitoring-and-logging.README.md](docs/monitoring-and-logging.RE
 
 ## CI/CD automation
 
-A GitHub Actions workflow which checks for new upstream version release tags and updates the downstream repo, can be found at:
+A GitHub Actions workflow which checks for new upstream version release tags and creates a PR to update the downstream repo, can be found at:
 
         .github/workflows/upgrade-check.yml.sample
 
 If activated, the workflow is scheduled by default to run every day at 9 AM UTC and can be triggered manually via the `workflow_dispatch` event. How to activate the workflow is detailed at the top of the file.
 
+Workflow uses [create-pull-request](https://github.com/peter-evans/create-pull-request) to handle the pull request action. See for action inputs.
+
 In order for GitHub actions to fetch workflow changes in `.github/workflows`, a PAT for each deployment must be provided.
 
 The following repository permissions must be set for the PAT: