fix gpu_particles_3d emitting finished signal on ready

scene/3d/gpu_particles_3d.cpp

@@ -92,7 +92,11 @@ void GPUParticles3D::set_one_shot(bool p_one_shot) {
 
 	if (is_emitting()) {
 		if (!one_shot) {
-			restart();
+			if (!use_fixed_seed) {
+				set_seed(Math::rand());
+			}
+
+			RenderingServer::get_singleton()->particles_restart(particles);
 		}
 	}
 }