Fix OpenUrlExternally potentially crashing applications due to misconfigurations (and log errors instead)

[yesseruser]

Added a try/catch statement to all overrides of the osu.Framework.Platform.GameHost.OpenUrlExternally method (in Desktop, IOS and Android platforms) for the bodies of the methods (excluding the url valid check).
Fixes ppy/osu#24696

[yesseruser]

@bdach All of your suggestions have been resolved.

[bdach]

The added Logger constant was massively weird and I've reverted it in 9bc79c6. The general advice is: if you don't see things like error messages extracted anywhere already, probably best to not do it.

Other than that, this is probably fine, as far as I can tell. I'm not sure the iOS variant makes sense, because I'm not sure if InvokeOnMainThread() marshals error correctly in a way that can even make the try-catch work. I can see a world wherein it does completely nothing and the try-catch should instead be moved inside the InvokeOnMainThread() callback. But I'll leave testing that to someone with an actual device.

[bdach]

see above

[yesseruser]

Okay, thank you.

[peppy]

I'm not sure the iOS variant makes sense, because I'm not sure if InvokeOnMainThread()

I don't think it does, but I also don't think it matters. This is mainly for desktop applications where it's been throwing.