添加学生签到无分组查询功能

web-infrastructure/src/main/resources/mapper/study/StudentSignMapper.xml

@@ -76,8 +76,6 @@
         s.name student_name,
         cl.name class_name,
         cl.training_location,
-        MAX(CASE WHEN ss.type = 1 THEN ss.face_url END) AS sign_face_url,
-        MAX(CASE WHEN ss.type = 2 THEN ss.face_url END) AS exam_face_url,
         u.user_avatar_url,
         s.user_id_card,
         s.phone,