The button isn't necessary. The only reason you'd want to avoid growth is if you wanted to avoid negative health penalties, and the negative health penalties are so small that you're better off growing and taking the penalty for low health than staying in positive health.
You only really want "avoid growth" in Civ 5 because negative happiness is such a bad place to be. In Beyond Earth, negative health isn't nearly as bad.
Imagine you have 0 health. This one point less means -10% to science and production. You wanna halt growth because you don't wanna this citizen.
Oh, there is not such an option. What a strategic freedom.
I won't oppose adding the button back in if you want to feel more "strategically free" or something, but it really isn't necessary.