CI: consolidate meson jobs
Rebase of !679 (closed) to add the comments I was looking for (and drop the commit that wasn't part of !418 (closed) and has its own MR), which itself is a rebase of !418 (closed).
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Rebase of !679 (closed) to add the comments I was looking for (and drop the commit that wasn't part of !418 (closed) and has its own MR), which itself is a rebase of !418 (closed).