How to include file references in your CI/CD components

What this post added

Introduces CI/CD Steps as a mechanism to allow CI/CD components to access and execute additional files (scripts, dependencies) stored within the same repository as the `step.yml` definition. Details the `run` keyword for components to execute steps and the `${{ step_dir }}` expression for referencing files within the step's cached repository. Highlights the difference between components (pipeline creation phase) and steps (job execution phase).