Add project template for Gitlab CI/CD components

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What does this MR do and why?

Add project template for Gitlab CI/CD components

• Related to #458953 (closed)
• Resolves #399199

File structure

• .gitlab-ci.yml

  include:
    # include the component located in the current project from the current SHA
    - component: $CI_SERVER_FQDN/$CI_PROJECT_PATH/my-component@$CI_COMMIT_SHA
      inputs:
        job_name: "component job of my-component"
        stage: build
  
  stages: [build, test, release]
  
  ensure-job-added:
    stage: test
    image: badouralix/curl-jq
    script:
      - |
        route="${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/pipelines/${CI_PIPELINE_ID}/jobs"
        count="$(curl --silent "$route" | jq 'map(select(.name | contains("component job of my-component"))) | length')"
        [ "$count" -eq 1 ]
  
  create-release:
    stage: release
    image: registry.gitlab.com/gitlab-org/release-cli:latest
    rules:
      - if: $CI_COMMIT_TAG
    script: echo "Creating release $CI_COMMIT_TAG"
    release:
      tag_name: $CI_COMMIT_TAG
      description: "Release $CI_COMMIT_TAG of components repository $CI_PROJECT_PATH"

• LICENSE

  MIT License
  
  Copyright (c) 2024 GitLab B.V.
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.

• README.md

  # Gitlab component template
  
  Includes a MVC structure to help you get started with [Gitlab CI/CD components](https://docs.gitlab.com/ee/ci/components/).
  
  - [ ] Replace this [README.md](README.md)
  - [ ] Replace [LICENCE](LICENCE)
  - [ ] Rename and adapt [templates/my-component.yml](templates/my-component.yml)
  - [ ] Adapt [.gitlab-ci.yml](.gitlab-ci.yml)

• templates/my-component.yml

  spec:
    inputs:
      data:
        default: "Hello world!"
      allow_failure:
        default: false
        type: boolean
      job_name:
        default: job
      stage:
        default: test
  
  ---
  $[[ inputs.job_name ]]:
    image:
      name: busybox:latest
    stage: $[[ inputs.stage ]]
    script:
      - echo "$[[ inputs.data ]]"
    allow_failure: $[[ inputs.allow_failure ]]

Screenshot

How to set up and validate locally

Create a new project using the "Gitlab CI/CD component" template.