Update CONTRIBUTING.md

Co-authored-by: Alex Chew <[email protected]>

Author: lizroth

CONTRIBUTING.md

@@ -51,7 +51,7 @@ [email protected] with any additional questions or comments.
 
 
 ## Security issue notifications
-If you discover a potential security issue in this project we ask that you notify AWS/Amazon Security via our [vulnerability reporting page](http://aws.amazon.com/security/vulnerability-reporting/). Please do **not** create a public github issue.
+If you discover a potential security issue in this project we ask that you notify AWS/Amazon Security via our [vulnerability reporting page](http://aws.amazon.com/security/vulnerability-reporting/). Please do **not** create a public GitHub issue.
 
 
 ## Licensing