Update notes copy-paste error

Author: heiskr

README.md

@@ -74,7 +74,7 @@ People use GitHub to build some of the most advanced technologies in the world.
 
 <!-- 
   <<< Author notes: Step 2 >>>
-  Start this step by acknowledging the first step.
+  Start this step by acknowledging the previous step.
   Define terms and link to docs.github.com.
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