evolve: apply prune update before creating obsolescence markers Prune used to compute the destination commit to update to after creating the obsolescence markers. This is a commit to prevent a bug that would occur with the changes in inhibit for transactions (next commit). Indeed, with that change in inhibit, when creating the obsolescence markers in prune, they would get inhibited right away and we wouldn't update to the first non obsolete parent but stay on the same node as its obsolescence would have been inhibited (bug).

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