fixed typo

Credit: @scarabedore
Close: #2161
Reviewed-by: @ruyadorno

Author: Sébastien Puech

docs/content/using-npm/scripts.md

@@ -6,7 +6,7 @@ description: How npm handles the "scripts" field
 
 ### Description
 
-The `"scripts"` property of of your `package.json` file supports a number of built-in scripts and their preset life cycle events as well as arbitrary scripts. These all can be executed by running `npm run-script <stage>` or `npm run <stage>` for short. *Pre* and *post* commands with matching names will be run for those as well (e.g. `premyscript`, `myscript`, `postmyscript`). Scripts from dependencies can be run with `npm explore <pkg> -- npm run <stage>`.
+The `"scripts"` property of your `package.json` file supports a number of built-in scripts and their preset life cycle events as well as arbitrary scripts. These all can be executed by running `npm run-script <stage>` or `npm run <stage>` for short. *Pre* and *post* commands with matching names will be run for those as well (e.g. `premyscript`, `myscript`, `postmyscript`). Scripts from dependencies can be run with `npm explore <pkg> -- npm run <stage>`.
 
 ### Pre & Post Scripts