Fix typo in @throw tag

@throw doesn't take an @link tag. ADS does not parse the later correctly :

https://developer.android.com/reference/android/window/OnBackInvokedDispatcher#registerOnBackInvokedCallback(int,%20android.window.OnBackInvokedCallback)

Change-Id: Ic50e6425393b41e9d8918d00cd1fe3489bb38817
Flag: DOCS_ONLY
Bug: N/A
Test: N/A