Minor cleanup in 10.2 regarding new tree creation

Author: td2014

book/10-git-internals/sections/objects.asc

@@ -188,9 +188,8 @@ You'll now create a new tree with the second version of `test.txt` and a new fil
 [source,console]
 ----
 $ echo 'new file' > new.txt
-$ git update-index --cacheinfo 100644 \
+$ git update-index --add --cacheinfo 100644 \
   1f7a7a472abf3dd9643fd615f6da379c4acb3e3a test.txt
-$ git update-index test.txt
 $ git update-index --add new.txt
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