Add possibility to setup multibranch

[maciekstosio]

We want to allow a multi-branch setup - what I mean by that the user can select processes (feature branch, main, release), and for each process user can select workflows. I imagine that at the beginning there will be select which processes we're adding (feature branch, main, release) - I assume we can be opinionated about the main branch naming and release strategy. Then our current selection is displayed for each process. Additionally, when we run the selected recipe we can show for which process it will be used.

[maciekstosio]

The description is my idea of how it could work, but I'm open to other options on how to resolve it from a UX perspective.

[km1chno]

I imagine the survey could look something like this:

Select processes you'd like to run in every pull request
(learn more about feature branch processes: /* link to docs */)
[ ] option a
[ ] option b

Select processes you'd like to run on main branch each time its head commit changes
(learn more about main branch processes: /* link to docs */)
[ ] option a
[ ] option b

Select processes you'd like to run on release branch each time new code is pushed to it
(learn more about release branch processes: /* link to docs */
[ ] option a
[ ] option b