[AutoBuild] Disallow prerelease numbers in versions of JLLs

[giordano]

As a matter of fact Pkg doesn't like them, I think it's better to automatically error our instead of having to tell users that they shouldn't use them.

Recent cases on Yggdrasil: https://github.com/JuliaPackaging/Yggdrasil/pull/5345#discussion_r953729854 and https://github.com/JuliaPackaging/Yggdrasil/pull/5344#discussion_r953604740.