ci: bump actions/download-artifact version

[renanrodrigo]

Why is this needed?

This PR solves all of our problems because it mitigates CVE-2024-42471.
Dependabot told us about this one, but I'm reopening here to let CI run and make sure all is good.
See #3289 for context.

Test Steps

Just let the CI run

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[renanrodrigo]

So, CI ran an the new version of the action is not pulling our artifact. Needs some investigation on why.

[renanrodrigo]

@paride I see there is an upload-artifact action too - maybe there is where the mismatch happens. This gotta be simpler than expected I guess

[renanrodrigo]

Solved - this is now good to go

[paride]

Thanks. Sorry with all the things around .5 I didn't get to this earlier.

[renanrodrigo]

@paride don't worry - it was easier than expected and at least we didn't waste your time (: