Fix typo in style guides

On line no 14, 2nd sentence, `them` was repeated twice.

javascript/javascript_in_the_real_world/linting.md

@@ -11,7 +11,7 @@ This section contains a general overview of topics that you will learn in this l
 
 ### Style guides
 
-Code style is important! Having a consistent set of style rules for things such as indentation or preferred quote style makes your code more maintainable and easier to read. There are several popular JavaScript style guides on the net that set standards for these types of things, and a little time spent looking through them them *will* make you a better developer. Have a little look at some popular style guides for an idea of what sort of things can be done to improve consistency:
+Code style is important! Having a consistent set of style rules for things such as indentation or preferred quote style makes your code more maintainable and easier to read. There are several popular JavaScript style guides on the net that set standards for these types of things, and a little time spent looking through them *will* make you a better developer. Have a little look at some popular style guides for an idea of what sort of things can be done to improve consistency:
 
 1. The [Airbnb Style Guide](https://github.com/airbnb/javascript) is one of the most popular. It is also very well formatted and easy to read.
 1. There is also a [JavaScript style guide used at Google](https://google.github.io/styleguide/jsguide.html).