Merge branch '412870-init-conversion' into 'master'

Initialize the conversion for ci_stages.pipeline_id

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/126650



Merged-by: Marius Bobin <mbobin@gitlab.com>
Approved-by: Marius Bobin <mbobin@gitlab.com>
Approved-by: Dzmitry Meshcharakou <12459192-dmeshcharakou@users.noreply.gitlab.com>
Reviewed-by: Marius Bobin <mbobin@gitlab.com>
Reviewed-by: Ethan Urie <eurie@gitlab.com>
Reviewed-by: Tianwen Chen <tchen@gitlab.com>
Reviewed-by: Dzmitry Meshcharakou <12459192-dmeshcharakou@users.noreply.gitlab.com>
Co-authored-by: Tianwen Chen <tchen@gitlab.com>