CI/CD Catalog Component Description in yml

Proposal

While I was implementing a new component, I was surprised to find that the specs do not allow for a description of the component itself. I have to document it separately in the README.

I propose a new optional attribute description allowing for a short component description which is shown in the CI/CD Catalog above the inputs. Similar to the existing inputs.

spec:
  description: "A short description of the component"
  inputs:
    # These are examples of inputs.
    job_name:
      default: job-template
    image:
      default: busybox:latest
    stage:
      default: test

---
# This is an example of a job using inputs
# use variables with this syntax : $[[ inputs.xxx ]]
$[[ inputs.job_name ]]:
  image: $[[ inputs.image ]]
  stage: $[[ inputs.stage ]]
  script:
    - echo "Starting job $[[ inputs.job_name ]]"
  rules:
    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
    - if: $CI_COMMIT_BRANCH && $CI_OPEN_MERGE_REQUESTS
      when: never
    - when: always