Support ghc 8.10.3 on Debian

[AlistairB]

Just thought I'd create this for tracking. Some mention of this is in haskell/docker-haskell#31

https://downloads.haskell.org/debian is only showing up to ghc 8.10.2

Happy to help if I can. Cheers ❤️

[AlistairB]

Missing versions are now there 🎉

[hvr]

@AlistairB Out of curiosity... how did you notice? I was too tired yesterday to followup and announce it yet... :-P

[AlistairB]

@hvr Haha, um obsessive checking ;) I just noticed after #474 was closed it all appeared in the ubunutu PPA, so I was keeping an eye on debian too.