Fix remaining clippy warnings in benchmarks #1276

Job	Run time
Build the fuzzers	1m 8s
Build and test uufuzz examples	29s
Fuzz (fuzz_date, false)	1m 16s
Fuzz (fuzz_test, true)	1m 54s
Fuzz (fuzz_echo, true)	1m 54s
Fuzz (fuzz_printf, true)	1s
Fuzz (fuzz_wc, false)	1m 22s
Fuzz (fuzz_expr, true)	1s
Fuzz (fuzz_seq, false)	1m 12s
Fuzz (fuzz_tr, false)	1s
Fuzz (fuzz_env, false)	1s
Fuzz (fuzz_cut, false)	32s
Fuzz (fuzz_parse_time, true)	32s
Fuzz (fuzz_split, false)	30s
Fuzz (fuzz_sort, false)	14s
Fuzz (fuzz_parse_glob, true)	1m 28s
Fuzz (fuzz_cksum, false)	1s
Fuzz (fuzz_parse_size, true)	1s
Fuzz (fuzz_seq_parse_number, true)	1m 54s
Fuzz (fuzz_non_utf8_paths, true)	1m 54s
Fuzzing Summary	5s
	16m 30s

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