Fix formatting in group_by.slt test file

Author: xiedeyantu

datafusion/sqllogictest/test_files/group_by.slt

@@ -5215,12 +5215,12 @@ from duplicate_grouping_sets
 group by grouping sets ((deptno, job), (deptno, sal), (deptno, job))
 order by deptno, job, sal, grouping(deptno), grouping(job), grouping(sal);
 ----
-10 CLERK   NULL NULL 0 0 1
-10 CLERK   NULL NULL 0 0 1
-10 NULL    1300 NULL 0 1 0
+10 CLERK NULL NULL 0 0 1
+10 CLERK NULL NULL 0 0 1
+10 NULL 1300 NULL 0 1 0
 20 MANAGER NULL NULL 0 0 1
 20 MANAGER NULL NULL 0 0 1
-20 NULL    3000 NULL 0 1 0
+20 NULL 3000 NULL 0 1 0
 
 statement ok
 drop table duplicate_grouping_sets;