Chore: fix latest clippy issues #4016

Job	Run time
openraft-test-bench (nightly)	1m 0s
openraft-features (nightly, generic-snapshot-data)	57s
stores (memstore)	1m 1s
stores (rocksstore)	6m 3s
Build (nightly, bench,serde,bt,singlethreaded)	54s
cluster-benchmark (cluster_benchmark)	1m 26s
stores (sledstore)	1m 8s
examples (stable, memstore)	38s
lint	11m 23s
examples (stable, raft-kv-memstore)	2m 46s
openraft-feature-test (nightly)	53s
external-stores (stores/rocksstore-v2)	7m 12s
examples (stable, raft-kv-memstore-generic-snapshot-data)	54s
openraft-feature-test (nightly, serde)	53s
examples (stable, raft-kv-memstore-opendal-snapshot-data)	1m 10s
openraft-test (stable, 0)	3m 24s
openraft-feature-test (nightly, single-term-leader)	52s
openraft-test (nightly, 30)	3m 23s
tests-feature-test (nightly)	2m 53s
openraft-test (nightly, 0, single-term-leader)	3m 15s
openraft-feature-test (nightly, single-term-leader,serde,singlethreaded)	56s
tests-feature-test (nightly, single-term-leader)	2m 53s
examples (stable, raft-kv-memstore-singlethreaded)	51s
tests-feature-test (nightly, loosen-follower-log-revert)	2m 51s
examples (stable, raft-kv-rocksdb)	8m 6s
examples (nightly, memstore)	1m 33s
examples (nightly, raft-kv-memstore)	2m 18s
examples (nightly, raft-kv-memstore-generic-snapshot-data)	1m 7s
examples (nightly, raft-kv-memstore-opendal-snapshot-data)	1m 24s
examples (nightly, raft-kv-memstore-singlethreaded)	1m 6s
examples (nightly, raft-kv-rocksdb)	12m 25s
	1h 27m 35s

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