Code review comment for lp://qastaging/~afrantzis/mir/initializer-list-style

I am ok with allowing both of the options in the original description.

I seem to have small a preference for:

===== Predominant style =====

class C(
    std::shared_ptr<int> const& a_pointer,
    std::shared_ptr<int> const& a_pointer,
    std::shared_ptr<int> const& a_pointer)
    : a_pointer{a_pointer},
      b_pointer{b_pointer},
      c_pointer{c_pointer}
{
}