Update 01_javascript_refresher.md

I assume this in an extra sentence that is duplicated.

01_Day_JavaScript_Refresher/01_javascript_refresher.md

@@ -236,7 +236,7 @@ Open the browser console to see the output from the console.log()
 #### External Script
 
 Similar to the internal script, the external script link can be on the header or body, but it is preferred to put it in the body.
-First, we should create an external JavaScript file with .js extension. All files ending with .js extension. All files ending with .js extension are JavaScript files. Create a file named introduction.js inside your project directory and write the following code and link this .js file at the bottom of the body.
+First, we should create an external JavaScript file with .js extension. All files ending with .js extension are JavaScript files. Create a file named introduction.js inside your project directory and write the following code and link this .js file at the bottom of the body.
 
 ```js
 console.log('Welcome to 30DaysOfJavaScript')