Fix broken link

jopemachine · web-flow · commit b9bb37c7f6ab · 2021-06-19T18:48:32.000+09:00
Existing link seems to be broken. I think https://webdriver.io/docs/browserobject/ might be more proper link.
diff --git a/README.md b/README.md
@@ -212,7 +212,7 @@ Spectron uses [WebdriverIO](http://webdriver.io) and exposes the managed
 `client` property on the created `Application` instances.
 
 The `client` API is WebdriverIO's `browser` object. Documentation can be found
-[here](http://webdriver.io/api.html).
+[here](https://webdriver.io/docs/browserobject/).
 
 Several additional commands are provided specific to Electron.
 
