Update 46.permutations.md

Author: azl397985856

problems/46.permutations.md

@@ -170,7 +170,7 @@ class Solution:
 - [39.combination-sum](./39.combination-sum.md)
 - [40.combination-sum-ii](./40.combination-sum-ii.md)
 - [47.permutations-ii](./47.permutations-ii.md)
-- [60.permutation-sequence](./60.permutation-sequence.md)(TODO)
+- [60.permutation-sequence](./60.permutation-sequence.md)
 - [78.subsets](./78.subsets.md)
 - [90.subsets-ii](./90.subsets-ii.md)
 - [113.path-sum-ii](./113.path-sum-ii.md)