Update README.md

Author: alesanchezr

exercises/01-Welcome/README.md

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+intro: https://www.youtube.com/watch?v=ooHdelGf0gI
+---
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 # Welcome to Loops
 
 Practice loops in javascript until you become confortable with it, I recomend watching [this short video about loops](https://www.youtube.com/watch?v=U3ZlQSOcOI0) before starting:
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 6. find.
 7. Loop dictionaries (object literals).
 
-Click `next →` when you are ready to start the exercises.
+Click `next →` when you are ready to start the exercises.