use dynamic pipeline for gitlab-ci instead of regenerate file each time
We can use dynamic pipeline (https://docs.gitlab.com/ee/ci/pipelines/parent_child_pipelines.html) instead of regenerate gitlab-ci.yml each time. c.f. https://www.objectif-libre.com/en/blog/2021/02/23/a-new-era-for-gitlab-ci-dynamic-child-pipelines/