Order::getPlacedTime() should cast the return value to an int

Let's target both getPlacedTime and getCompletedTime. Not sure about setting the return type on the interface though - I am all for having it, but this will break things for those who override/decorate the entity class

Actually, more in favor of increasing the scope and doing this once for all... This change is long overdue and should have been part of 3.0.0

Ok the change shouldn't be disruptive as I finally skipped return types, will go ahead and merge this.

Is it fixing my issue https://www.drupal.org/project/commerce/issues/3485574 🐛 Placed time return string but should be int Active ?