Update 0162.md (#1257)

Author: dawoonchung

aip/general/0162.md

@@ -234,7 +234,7 @@ current point in time eliminates that issue.
 
 ## History
 
-### Switching from from a collection extension to a subcollection
+### Switching from a collection extension to a subcollection
 
 In 2023-09, revisions are abstracted as a nested resource collection. Prior to
 this, revisions are more like extension of an existing resource by using `@`