modified () new commits

是因为那个目录下有新的commit,
这是git diff
就会出现
@@ -1 +1 @@
-Subproject commit 9ea1cebe3dc529ba3861d87c818f045362c40484
+Subproject commit 04ab7af68536ac2c80fd6c08a6fd3620d3409891
然后cd到那个目录，
Git reset --hard 9ea1cebe3dc529ba3861d87c818f045362c40484
然后cd到最外层的dir
Git status就干净了。