doc: add islandryu to collaborators

Fixes: #58559
PR-URL: #58714
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>

Author: islandryu

README.md

@@ -355,6 +355,8 @@ For information about the governance of the Node.js project, see
   **Harshitha K P** <<harshitha014@gmail.com>> (she/her)
 * [himself65](https://github.com/himself65) -
   **Zeyu "Alex" Yang** <<himself65@outlook.com>> (he/him)
+* [islandryu](https://github.com/islandryu) -
+  **Ryuhei Shima** <<shimaryuhei@gmail.com>> (he/him)
 * [jakecastelli](https://github.com/jakecastelli) -
   **Jake Yuesong Li** <<jake.yuesong@gmail.com>> (he/him)
 * [JakobJingleheimer](https://github.com/JakobJingleheimer) -