Added return types to order relationship methods

src/Order/Models/Order.php

@@ -17,6 +17,8 @@
 use Carbon\Carbon;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Support\Collection;
 use Konekt\Address\Models\AddressProxy;
 use Konekt\Enum\Eloquent\CastsEnums;
@@ -124,17 +126,17 @@ public function getItems(): Traversable
  return $this->items;
  }
 
- public function billpayer()
+ public function billpayer(): BelongsTo
  {
  return $this->belongsTo(BillpayerProxy::modelClass());
  }
 
- public function shippingAddress()
+ public function shippingAddress(): BelongsTo
  {
  return $this->belongsTo(AddressProxy::modelClass());
  }
 
- public function items()
+ public function items(): HasMany
  {
  return $this->hasMany(OrderItemProxy::modelClass());
  }