Not all tarballs are uploaded when GPU-enabled builds are done

[casparvl]

In this pr there are plenty of tarballs that didn't get uploaded, e.g. this one. I think in the end, we get 14 tarballs, since each bot only uploaded 'the latest' for each architecture.

But what does that mean - latest? It seems to mean latest for each CPU architecture. I.e. probably if a zen4+cc80 tarball was produced after a zen4+cc70 tarball, it only uploads the first, as it probably only looks at CPU architecture, then says "I'll upload only the latest of these two".

We should change the code for the 'latest' logic to also consider tarballs for different GPU targets to be, actually, different.

[casparvl]

The issue is actually not in the eessi-bot-software-layer, but it's the tarball names that are picked here https://github.com/EESSI/software-layer-scripts/blob/41f3775bfe214ecc51af2ea88f914d93414ed87b/bot/build.sh#L274 which don't contain any reference to the GPU arch being built for.

[casparvl]

Fixed in EESSI/software-layer-scripts#63