composite action allows you to combine multiple workflow steps within one action
Github Action RunsCreating a composite action - GitHub Docs
In this guide, you'll learn about the basic components needed to create and use a packaged composite action. To focus this guide on the components needed to package the action, the functionality of the action's code is minimal. The action prints "Hello World" and then "Goodbye", or if you provide a custom name, it prints "Hello [who-to-greet]" and then "Goodbye".
https://docs.github.com/en/actions/creating-actions/creating-a-composite-action

GitHub Actions: reusable workflows is generally available | The GitHub Blog
GitHub Actions keeps getting better and better for teams of all shapes and sizes. Over the past month, thousands of repositories have used the beta of reusable workflows to reduce duplication and increase consistency, including many large enterprises. We've released a number of improvements since the beta began in October.
https://github.blog/2021-11-29-github-actions-reusable-workflows-is-generally-available/


Seonglae Cho