Point Apple Safari Vendor status to W3C WebDriver protocol supported commands (#1757)

In this commit we update the Safari vendor status document to point to the set of commands supporting the W3C WebDriver protocol. The previous link redirects to [macOS WebDriver Commands for Safari 11.1 and earlier](https://developer.apple.com/documentation/webkit/macos_webdriver_commands_for_safari_11_1_and_earlier?language=objc), which highlights the WebDriver Commands supporting the Selenium JSON Wire Protocol instead.

Signed-off-by: Abrar Rahman Protyasha <[email protected]>

Author: aprotyas

README.md

@@ -46,7 +46,7 @@ Vendor status documents
 
 * [Mozilla Firefox](https://bugzilla.mozilla.org/showdependencytree.cgi?id=721859&hide_resolved=1)
 * [Microsoft Edge](https://docs.microsoft.com/en-us/microsoft-edge/webdriver#w3c-webdriver)
-* [Apple Safari](https://developer.apple.com/library/content/documentation/NetworkingInternetWeb/Conceptual/WebDriverEndpointDoc/Commands/Commands.html)
+* [Apple Safari](https://developer.apple.com/documentation/webkit/macos_webdriver_commands_for_safari_12_and_later)
 * [WebKit GTK port](http://trac.webkit.org/wiki/WebDriverStatus)
 * [Selenium IEDriverServer](https://github.com/SeleniumHQ/selenium/wiki/W3C-WebDriver-Status)
 * [Chrome](https://chromium.googlesource.com/chromium/src/+/master/docs/chromedriver_status.md)