Fix order of linker custom steps

[sbomer]

The order in which the linker processes custom steps is being changed (fixed) in dotnet/linker#2082. When we get an update with that change, we will need to change the order of our custom steps to match.

I think only these two steps need to be swapped:

https://github.com/xamarin/xamarin-android/blob/ca51adbc390c0d8be714ff0738b47f38266b1002/src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.ILLink.targets#L82-L93