feat: add factory for models

app/Models/MedicalCenter.php

@@ -2,12 +2,15 @@
 
 namespace App\Models;
 
+use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 
 class MedicalCenter extends Model
 {
+    use HasFactory;
+
     public $fillable = ['name', 'city_id', 'address', 'phone_number'];
 
     public function users(): HasMany