Register IServiceProviderIsService interface

[rikrak]

Updates to VS/dotnet have broken some codebases that use Unity as the IoC container[1][2] due to the IServiceProviderIsService interface not being registered. Feels like it would make sense for this to be registered in the ServiceProviderFactory along with other similar interfaces.

[1] https://developercommunity.visualstudio.com/t/Upgrade-to-VS-v17111-breaks-swagger:-/10728128
[2] https://developercommunity.visualstudio.com/t/With-the-latest-upgrade-to-VS-2022-v179/10540911?sort=newest&viewtype=all