readme: fix authHandler value type

Author: mscdex

README.md

@@ -800,7 +800,7 @@ You can find more examples in the `examples` directory of this repository.
 
     * **tryKeyboard** - _boolean_ - Try keyboard-interactive user authentication if primary user authentication method fails. If you set this to `true`, you need to handle the `keyboard-interactive` event. **Default:** `false`
 
-    * **authHandler** - _function_ - Function with parameters `(methodsLeft, partialSuccess, callback)` where `methodsLeft` and `partialSuccess` are `null` on the first authentication attempt, otherwise are an array and boolean respectively. Return or call `callback()` with either the name of the authentication method or an object containing the method name along with method-specific details to try next (return/pass `false` to signal no more methods to try). Valid method names are: `'none', 'password', 'publickey', 'agent', 'keyboard-interactive', 'hostbased'`. **Default:** function that follows a set method order: None -> Password -> Private Key -> Agent (-> keyboard-interactive if `tryKeyboard` is `true`) -> Hostbased
+    * **authHandler** - _mixed_ - Either an array of objects as described below or a function with parameters `(methodsLeft, partialSuccess, callback)` where `methodsLeft` and `partialSuccess` are `null` on the first authentication attempt, otherwise are an array and boolean respectively. Return or call `callback()` with either the name of the authentication method or an object containing the method name along with method-specific details to try next (return/pass `false` to signal no more methods to try). Valid method names are: `'none', 'password', 'publickey', 'agent', 'keyboard-interactive', 'hostbased'`. **Default:** function that follows a set method order: None -> Password -> Private Key -> Agent (-> keyboard-interactive if `tryKeyboard` is `true`) -> Hostbased
 
         * When returning or calling `callback()` with an object, it can take one of the following forms: