[tlbuild] auxiliary binaries for pretest

[Akira Kakuto]

Hi Karl,

On 2021/02/26 8:29, Karl Berry wrote:
> win32: lz4.exe wget.exe xz.exe

wget.exe was updated (1.21.1).
xz.exe was updated (5.2.5).
I have now updated lz4.exe (v1.9.3).

Thanks,
Akira