Cargo audit fix #1608

Job	Run time
check	3m 20s
clippy	3m 59s
test	11m 16s
audit	22s
rustfmt	7s
integration-test-five-nodes	13m 10s
cross-aarch64	1m 26s
cross-armv7	1m 31s
integration-test-db-migration	12m 39s
integration-test-althea-payment	18m 20s
integration-test-debts	17m 41s
integration-test-eth-payments	13m 29s
integration-test-multi-exit	12m 55s
integration-test-validate-contract	12m 37s
	2h 2m 52s

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