include gamepad plugin in README

README.md

@@ -23,6 +23,7 @@ Plugin/Extension | Contributor | Description
 [audio-multi-response](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-audio-multi-response/README.md) | [Adam Richie-Halford](https://github.com/richford) | This plugin collects responses to an audio file using both button clicks and key presses.
 [audio-swipe-response](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-audio-swipe-response/README.md) | [Adam Richie-Halford](https://github.com/richford) | This plugin collects responses to an audio file using swipe gestures and keyboard responses.
 [corsi-blocks](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-corsi-blocks/README.md) | [Josh de Leeuw](https://github.com/jodeleeuw) | This plugin displays a configurable Corsi blocks task and records a series of click responses.
+[gamepad](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-gamepad/README.md) | [Shaobin Jiang](https://github.com/Shaobin-Jiang) | This plugin allows one to use gamepads in a jsPsych experiment.
 [html-choice](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-html-choice/README.md) | [Younes Strittmatter](https://github.com/younesStrittmatter) | This plugin displays clickable html elements that can be used to present a choice.
 [html-multi-response](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-html-multi-response/README.md) | [Adam Richie-Halford](https://github.com/richford) | This plugin collects responses to an arbitrary HTML string using both button clicks and key presses.
 [html-swipe-response](https://github.com/jspsych/jspsych-contrib/blob/main/packages/plugin-html-swipe-response/README.md) | [Adam Richie-Halford](https://github.com/richford) | This plugin collects responses to an arbitrary HTML string using swipe gestures and keyboard responses.