Fix typo

Author: Muhammad Rehan Saeed

.github/CONTRIBUTING.md

@@ -2,7 +2,7 @@
 
 # Steps to contribute
 
- If you want to make If it's a small change, go ahead and raise a pull request, otherwise follow these steps:
+ If you want to make a small change, go ahead and raise a pull request, otherwise follow these steps:
 
 1. View the [Issues](https://github.com/RehanSaeed/Schema.NET/issues) page to see a To-Do list of things to be implemented.
 2. Raise an issue or comment on an existing issue with what you want to contribute if one does not already exist.