Fix crash when using sizeof, instance_sizeof, or offsetof as a type arg

[keidax]

This doesn't prevent using sizeof in some cases. Something like this works still:

foo : Int32[sizeof(UInt8)] = Int32.static_array(1)

Poking around in the compiler code for the first time, I couldn't see a way to expand this functionality to also work for other cases. And based on comments on the related issues, maybe it doesn't make sense to do so. So I decided to just fix the ugly crash message. I believe this resolves #8858, while leaving #5427 open for future work.

The small parser change just allows the error message to point to the right part of the line, like

 1 | alias Foo = Array(sizeof(Int32))
                       ^
Error: can't use sizeof(Int32) as a generic type argument

[beta-ziliani]

Awesome, thanks!

[beta-ziliani]

Please @keidax do not force-push the branch, as we lost track of what did we review. Thanks!

[keidax]

@beta-ziliani I was just rebasing the branch to fix the failing CI, I won't force push in the future

[straight-shoota]

Merging master is preferred over rebasing because that's more transparent. We squash merge in the end, so it doesn't matter to have merge commits in the branch.