Fix typo

Summary:
<!--
Thank you for sending the PR! We appreciate you spending the time to work on these changes.

Help us understand your motivation by explaining why you decided to make this change.

You can learn more about contributing to React Native here: http://facebook.github.io/react-native/docs/contributing.html

Happy contributing!

-->

I saw a word missing; I just wanted to correct the typo.

No testing needed for a typo in the documentation
Closes #15393

Differential Revision: D5601466

Pulled By: javache

fbshipit-source-id: 7cfb6ba957ac4053fd8645af419a7be2361c6c75

docs/LinkingLibraries.md

@@ -24,7 +24,7 @@ to `require` it. Other libraries also rely on some native code, in that case
 you'll have to add these files to your app, otherwise the app will throw an
 error as soon as you try to use the library._
 
-## Here the few steps to link your libraries that contain native code
+## Here are the few steps to link your libraries that contain native code
 
 ### Automatic linking