重构试卷相关内容

Entities/Contracts/SubmissionDetail.cs

@@ -52,7 +52,6 @@ namespace Entities.Contracts
 		[Column("deleted")]
 		public bool IsDeleted { get; set; }
 
-		// Navigation Properties
 		public Submission Submission { get; set; }
 		public User User { get; set; }
 		public AssignmentQuestion AssignmentQuestion { get; set; }