docs: update list of contributors

PR-URL: #7856
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: stdlib-bot

CONTRIBUTORS

@@ -13,6 +13,7 @@ Abhishek G <166795493+AbhishekG-Codes@users.noreply.github.com>
 Abhishek Jain <40913033+abhishekblue@users.noreply.github.com>
 Adarsh Palaskar <adarshpalaskar99@gmail.com>
 Aditya Sapra <adityaework@gmail.com>
+Aditya Singh <adityasinghk099@gmail.com>
 Ahmed Atwa <Ahmedatwa866@yahoo.com>
 Ahmed Kashkoush <ahmedkashkoush464@gmail.com>
 Ahmed Khaled <kahmd1444@gmail.com>