fix tests

app/Models/Exam.php

@@ -2,8 +2,6 @@
 
 namespace App\Models;
 
-use App\Models\BaseModel;
-
 class Exam extends BaseModel
 {
     protected $table = 'exams';
@@ -16,6 +14,7 @@ class Exam extends BaseModel
      * We'll keep auto created_at, no updated_at:
      */
     public $timestamps = true;
+
     const UPDATED_AT = null; // ✅ no updated_at column
 
     protected $fillable = [
@@ -27,8 +26,8 @@ class Exam extends BaseModel
     ];
 
     protected $casts = [
-        'student_id'       => 'integer',
-        'school_id'        => 'integer',
+        'student_id' => 'integer',
+        'school_id' => 'integer',
         'class_section_id' => 'integer',
     ];
 
@@ -42,4 +41,4 @@ class Exam extends BaseModel
     {
         return $this->belongsTo(ClassSection::class, 'class_section_id');
     }
-}
+}