Adding new initialization Method

If you want to have two traits at the same time with an alias like this

use SyliusSpecalPricePlugin {
__construct as private initSpecialPrices;
}
use SomeOtherPlugin {
__construct as private initOtherPlugin;
}

Then PHP will run the Constructor of the Special Price plugin for both of them:

initSpecialPrices => SyliusSpecalPricePlugin::__construct
initOtherPlugin => SyliusSpecalPricePlugin::__construct

This is why we now have a dedicated non constructor method.