docs: update docs for wechat oauth provider (#599)

docs/provider/oauth/Wechat.md

@@ -18,9 +18,9 @@ The WeChat provider offers two different sets of keypairs:
 
 - The first keypair (`Client ID`, `Client Secret`) is for the `WeChat Open Platform (微信开放平台)` and is designed for the PC login scenario. It allows you to display a QR code in the PC browser, which users can scan using the WeChat app on their mobile phone to sign in.
 
-- The second keypair (`Client ID 2`, `Client Secret 2`) is for the `WeChat Media Platform (微信公众平台)` and is intended for the inside-WeChat-app login scenario. It enables users to log in with the WeChat built-in browser inside the WeChat mobile app, which will redirect them to your `WeChat Official Account (微信公众号)` to log in. Please note that WeChat does not support logging in outside of the WeChat app in other mobile browsers or apps. This limitation is imposed by WeChat and not by Casdoor.
+- The second keypair (`Client ID 2`, `Client Secret 2`) and `Access Token` field is for the `WeChat Media Platform (微信公众平台)` and is intended for the inside-WeChat-app login scenario.`Access Token` field is the `Token` you fill in the `server configuration` of the `WeChat Media Platform (微信公众平台)`. It enables users to log in with the WeChat built-in browser inside the WeChat mobile app, which will redirect them to your `WeChat Official Account (微信公众号)` to log in. Please note that WeChat does not support logging in outside of the WeChat app in other mobile browsers or apps. This limitation is imposed by WeChat and not by Casdoor.
 
-If you fill in the second keypair (`Client ID 2`, `Client Secret 2`) and enable the `Enable QR code` switch, Casdoor will ask the user to follow the WeChat official account (微信公众号) before proceeding with the login process when the user clicks on the WeChat button to log in. It's important to note that this functionality is only available in the PC login scenario because a mobile phone cannot scan the QR code by itself. When used in the mobile scenario (i.e., the WeChat built-in browser inside the WeChat mobile app), Casdoor will automatically skip this step.
+If you fill in the second keypair (`Client ID 2`, `Client Secret 2`), fill the `Access Token` field and enable the `Enable QR code` switch, Casdoor will ask the user to follow the WeChat official account (微信公众号) before proceeding with the login process when the user clicks on the WeChat button to log in. It's important to note that this functionality is only available in the PC login scenario because a mobile phone cannot scan the QR code by itself. When used in the mobile scenario (i.e., the WeChat built-in browser inside the WeChat mobile app), Casdoor will automatically skip this step.
 
 :::tip