You must have access to Epic’s private Unreal Engine GitHub repository in order to use that link. Unfortunately, there’s no quick workaround—cherry-picking the changes is tedious and error-prone, so I don’t recommend it.
I’ve reported this issue to Epic multiple times, but each submission has been rejected. It seems they aren’t even aware it’s happening. This is a critical blocker for anyone doing iOS development, which clearly conflicts with Epic’s stated goal of improving mobile support.
If you’re affected, please also file a bug report here:
https://www.unrealengine.com/en-US/support/report-a-bug