message: doc: update developer notes for removal of MakeUnique
diff: @@ -594,11 +594,6 @@ Common misconceptions are clarified in those sections:
  - *Rationale*: This avoids memory and resource leaks, and ensures exception safety.
  -- Use `MakeUnique()` to construct objects owned by `unique_ptr`s.
  -
  - - *Rationale*: `MakeUnique` is concise and ensures exception safety in complex expressions.
  - `MakeUnique` is a temporary project local implementation of `std::make_unique` (C++14).
  -
  C++ data structures
  --------------------
  