Julia 1.3.1 cannot automatically install

@rvignolo what does the following say for you:

using Pkg
Pkg.PlatformEngines.probe_platform_engines!(; verbose=true)
mktempdir() do dir
    url = "https://github.com/JuliaBinaryWrappers/Expat_jll.jl/releases/download/Expat-v2.2.7+0/Expat.v2.2.7.x86_64-w64-mingw32.tar.gz"
    Pkg.PlatformEngines.download(url, joinpath(dir, "test.tar.gz"); verbose=true)
end