Move test of stackoverflow with close(::Channel) to stack_overflow.jl (#49702)
Per @vtjnash's comment here:
https://github.com/JuliaLang/julia/pull/49508/files/bca5ac79d04fb2a95f3b9a7b7448fe5b478f950b#r1186161259
> the handling of this error is quite bad and sometimes ends up breaking
> the process (as I found out today trying to debug something completely
> unrelated)
This is a Tests-only PR