Change pipeline schedule button text

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/147058



Merged-by: Mireya Andres <mandres@gitlab.com>
Approved-by: Marcel van Remmerden <mvanremmerden@gitlab.com>
Approved-by: Jay Montal <jmontal@gitlab.com>
Approved-by: Panos Kanellidis <pkanellidis@gitlab.com>
Approved-by: Stanislav Lashmanov <slashmanov@gitlab.com>
Approved-by: Mireya Andres <mandres@gitlab.com>
Reviewed-by: Panos Kanellidis <pkanellidis@gitlab.com>
Co-authored-by: Payton Burdette <pburdette@gitlab.com>