Fix prepare-devnet script on MacOS #6095

Job	Run time
Build & test (plutus-cbor)	1m 7s
Build & test (plutus-merkle-tree)	1m 10s
Build & test (hydra-plutus)	1m 32s
Build & test (hydra-tui)	3m 19s
Build & test (hydra-node)	8m 14s
Build & test (hydra-tx)	1m 50s
Build haddock using nix	1m 5s
Build & test (hydra-cluster)	8m 40s
Benchmarks (hydra-node, tx-cost, --output-directory $(pwd)/../benchmarks)	1m 54s
Build specification using nix	1m 27s
nix flake check	5m 6s
Benchmarks (hydra-node, micro, -o $(pwd)/../benchmarks/ledger-bench.html)	1m 34s
Compute cost differences	2m 46s
Benchmarks (hydra-cluster, bench-e2e, datasets datasets/1-node.json datasets/3-nodes.json --outpu...	3m 56s
Benchmarks (plutus-merkle-tree, on-chain-cost, $(pwd)/../benchmarks)	1m 18s
Publish benchmark results	0s
Publish test results	0s
Documentation	0s
	44m 58s

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