ci: ubuntu-latest-x86 uses julia-x64

[inkydragon]

We forgot to specify the julia version:

SHA.jl/.github/workflows/CI.yml

Lines 38 to 40 in 0b76d04

	- uses: julia-actions/setup-julia@latest
	with:
	version: ${{ matrix.julia-version }}

This has led to us not actually testing SHA.jl on x86 platforms.

https://github.com/JuliaCrypto/SHA.jl/actions/runs/12268396845/job/34230160480#step:3:5

Run julia-actions/setup-julia@latest
  with:
    version: nightly
    include-all-prereleases: false
    arch: default
    show-versioninfo: false
/usr/bin/tar xf /home/runner/work/_temp/abfeaad8-571c-433d-9d34-a5bcf7cb8460 --strip-components=1 -C /opt/hostedtoolcache/julia/nightly/x64
/opt/hostedtoolcache/julia/nightly/x64/bin/julia --compile=min -O0 -e using InteractiveUtils; versioninfo()
Julia Version 1.1[2](https://github.com/JuliaCrypto/SHA.jl/actions/runs/12268396845/job/34230160480#step:3:2).0-DEV.1742
Commit 9160e048b[3](https://github.com/JuliaCrypto/SHA.jl/actions/runs/12268396845/job/34230160480#step:3:3)4 (2024-12-10 14:39 UTC)
Build Info:
  Official https://julialang.org release
Platform Info:
  OS: Linux (x86_6[4](https://github.com/JuliaCrypto/SHA.jl/actions/runs/12268396845/job/34230160480#step:3:4)-linux-gnu)
  CPU: 4 × AMD EPYC 7763 64-Core Processor
  WORD_SIZE: [6](https://github.com/JuliaCrypto/SHA.jl/actions/runs/12268396845/job/34230160480#step:3:6)4
  LLVM: libLLVM-18.1.[7](https://github.com/JuliaCrypto/SHA.jl/actions/runs/12268396845/job/34230160480#step:3:8) (ORCJIT, znver3)
Threads: 1 default, 0 interactive, 1 GC (on 4 virtual cores)

[inkydragon]

Closed by #117