Apply rustfmt and fix Clippy warnings #826

Job	Run time
test-no-std	12s
test-no-std	12s
test-miri	3m 41s
test-miri	3m 41s
test-cross (ubuntu-latest, powerpc-unknown-linux-gnu, stable)	1m 34s
test-cross (ubuntu-latest, powerpc-unknown-linux-gnu, stable)	1m 34s
Check doc	1m 3s
Check doc	1m 3s
test-ios	31s
test-ios	31s
test (ubuntu-latest, x86_64-unknown-linux-gnu, stable)	50s
test (ubuntu-latest, x86_64-unknown-linux-gnu, stable)	50s
test (macos-latest, x86_64-apple-darwin, stable)	57s
test (macos-latest, x86_64-apple-darwin, stable)	57s
test (windows-latest, x86_64-pc-windows-gnu, stable)	1m 28s
test (windows-latest, x86_64-pc-windows-gnu, stable)	1m 28s
test (windows-latest, x86_64-pc-windows-msvc, beta)	1m 31s
test (windows-latest, x86_64-pc-windows-msvc, beta)	1m 31s
test (ubuntu-latest, x86_64-unknown-linux-gnu, MSRV, 1.61.0)	2m 50s
test (ubuntu-latest, x86_64-unknown-linux-gnu, MSRV, 1.61.0)	2m 50s
test (ubuntu-latest, sudo apt-get update ; sudo apt install gcc-multilib, i686-unknown-linux-gnu,...	1m 44s
test (ubuntu-latest, sudo apt-get update ; sudo apt install gcc-multilib, i686-unknown-linux-gnu,...	1m 44s
test (ubuntu-latest, x86_64-unknown-linux-gnu, nightly, minimal_versions)	11s
test (ubuntu-latest, x86_64-unknown-linux-gnu, nightly, minimal_versions)	10s
	33m 3s

Provide feedback