let's say I have pipeline_1 which has 10 tasks in it.
and I also have pipeline_2 with has 10 tasks in it.
I want a new_pipeline that will run pipeline_1 and after that will run pipeline_2.

If I cannot do pipeline of pipelines, it means that I need to create a pipeline containing 20 tasks using add_step !
and In the future if I would like to add pipeline_3 to all of this, I'll need again to use add_step to all the 20 task + the ones of pipeline_3.

I makes all the process very uncomfortable as we scales to larger automations and tasks. So I need a way to make it simple and more readable using a pipeline of pipelines