学校列表顾问列表为空或者长度为0时候返回统一

TEAMModelBI/Models/AssistSchool.cs

@@ -19,7 +19,7 @@ namespace TEAMModelBI.Models
         public int scale { get; set; }
         public string standard { get; set; }
         public string areaId { get; set; }
-        public List<SchoolTeacherRoles> assists { get; set; }
+        public List<SchoolTeacherRoles> assists { get; set; } = new List<SchoolTeacherRoles>();
         public int serial { get; set; } //软体
         public int service { get; set; } //服务
         public int hard { get; set; } //硬体