Fix warning about git restore command

Author: Fabien-jrt

book/02-git-basics/sections/undoing.asc

@@ -229,7 +229,7 @@ Changes to be committed:
 
 [IMPORTANT]
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-It's important to understand that `git restore --staged <file>` is a dangerous command.
+It's important to understand that `git restore <file>` is a dangerous command.
 Any local changes you made to that file are gone -- Git just replaced that file with the most recently-committed version.
 Don't ever use this command unless you absolutely know that you don't want those unsaved local changes.
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