Multiple minor lint fixes #2720

Job	Run time
minimal	10s
rustfmt-clippy	29s
msrv	46s
docs	20s
check-cfg	22s
quickchecking	11s
test-book	6s
test (ubuntu-latest, 9.0, 0, 0, 0, 0)	1m 46s
test-expectations (ubuntu-latest)	38s
test (ubuntu-latest, 9.0, 0, 0, 1, 0)	1m 38s
test-no-headers	23s
test-expectations (macos-latest)	37s
test (ubuntu-latest, 9.0, 0, 1, 0, 0)	1m 39s
test (ubuntu-latest, 9.0, 0, 1, 1, 0)	1m 37s
test (ubuntu-latest, 9.0, 1, 0, 0, 0)	2m 10s
test (ubuntu-latest, 9.0, 1, 0, 1, 0)	2m 7s
test (ubuntu-latest, 9.0, 1, 1, 0, 0)	2m 12s
test (ubuntu-latest, 9.0, 1, 1, 1, 0)	2m 11s
test (ubuntu-latest, 16.0, 0, 0, 0, 0)	3m 57s
test (ubuntu-latest, 16.0, 0, 0, 1, 0)	4m 13s
test (ubuntu-latest, 16.0, 0, 1, 0, 0)	4m 0s
test (ubuntu-latest, 16.0, 0, 1, 1, 0)	3m 58s
test (ubuntu-latest, 16.0, 1, 0, 0, 0)	4m 48s
test (ubuntu-latest, 16.0, 1, 0, 1, 0)	5m 16s
test (ubuntu-latest, 16.0, 1, 1, 0, 0)	4m 31s
test (ubuntu-latest, 16.0, 1, 1, 1, 0)	4m 38s
test (ubuntu-latest, 16.0, 0, 0, 1)	2m 27s
test (macos-latest, 16.0, 0, 0, 0)	2m 0s
success	1s
	59m 11s

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