Caching warning when caching is used on windows, but no cache exists

[IanButterworth]

See https://github.com/JuliaWeb/HTTP.jl/actions/runs/11984291113/job/33414881625#step:5:51

I guess if no cache is restored we're not making the depot properly or not detecting it existing properly.

[IanButterworth]

Run mkdir -p C:\Users\runneradmin/.julia
  mkdir -p C:\Users\runneradmin/.julia
  du -shc C:\Users\runneradmin/.julia/* || true
  shell: C:\Program Files\Git\bin\bash.EXE --noprofile --norc -e -o pipefail {0}
du: cannot access 'C:Usersrunneradmin/.julia/*': No such file or directory
0	total
Run if [ -d "C:\Users\runneradmin/.julia/registries" ] && [ -n "$(ls -A "C:\Users\runneradmin/.julia/registries")" ]; then
  if [ -d "C:\Users\runneradmin/.julia/registries" ] && [ -n "$(ls -A "C:\Users\runneradmin/.julia/registries")" ]; then
    echo "Registries directory exists and is non-empty. Updating any registries"
    julia -e "import Pkg; isdefined(Pkg, :Registry) && Pkg.Registry.update();"
  else
    echo "Registries directory does not exist or is empty. Skipping registry update"
  fi
  shell: C:\Program Files\Git\bin\bash.EXE --noprofile --norc -e -o pipefail {0}