chore: deflake duplicate attestations and proposals slash tests#21294

PhilWindle merged 2 commits intomerge-train/spartanAztecProtocol/aztec-packages:merge-train/spartanfrom

mr/deflake-duplicate-proposal-and-attestation-slash-testsAztecProtocol/aztec-packages:mr/deflake-duplicate-proposal-and-attestation-slash-testsCopy head branch name to clipboard