Observers and component hooks triggered from is_a out of order

[nimble0]

Describe the bug
Observers and component hooks do not trigger in order (as in all component hooks before all observers) when triggered from instantiating a prefab.

To Reproduce
Edited flecs/examples/cpp/prefabs/src/main.cpp

#include <basics.h>
#include <iostream>


struct Defense {
	double value;
};

struct Armour {
	double value;
};

int main() {
	flecs::world ecs;

	ecs.component<Defense>()
		.on_set([](flecs::entity, Defense&)
		{
			std::cout << "Defense on_set hook trigger\n";
		});

	ecs.component<Armour>()
		.on_set([](flecs::entity, Armour&)
		{
			std::cout << "Armour on_set hook trigger\n";
		});

	ecs.observer<const Defense, Armour>("CalculateArmour")
		.event(flecs::OnSet)
		.each([&](flecs::entity, const Defense& defense, Armour& armour)
		{
			armour.value = 1.0 / defense.value;
			std::cout << "observer trigger\n";
		});

	// Create a SpaceShip prefab with a Defense component.
	std::cout << "make prefab\n";
	flecs::entity SpaceShip = ecs.prefab("SpaceShip")
		.set<Defense>({ 50 })
		.set(Armour{});

	// Create a prefab instance
	std::cout << "\nmake prefab instance\n";
	flecs::entity inst = ecs.entity("my_spaceship").is_a(SpaceShip);
}

Expected output

make prefab
Defense on_set hook trigger
Armour on_set hook trigger

make prefab instance
Defense on_set hook trigger
Armour on_set hook trigger
observer trigger

Actual output

make prefab
Defense on_set hook trigger
Armour on_set hook trigger

make prefab instance
Defense on_set hook trigger
observer trigger
Armour on_set hook trigger