juliaup cannot install / add PRs

[wheeheee]

As in title. Have checked other platforms. For example:

juliaup add pr62217

WARNING: Note that unmerged PRs may not have been reviewed for security issues etc.
         Review code at https://github.com/JuliaLang/julia/pull/62217

  Installing Julia pr62217-win64
Error: Failed to download and extract pr or nightly: Failed to download from `https://julialangnightlies-s3.julialang.org/bin/windows/x86_64/julia-pr62217-windows-x86_64.tar.gz`.

[IanButterworth]

The PR binary uploading system is currently offline. Hopefully back soon.