Refactor/fix clippy errors #3978

Job	Run time
Init	5s
Examples (examples/actix_example)	2m 53s
Rustfmt	14s
Examples (examples/actix3_example)	2m 42s
Clippy	1m 38s
Unit Test	3m 7s
Examples (examples/axum_example)	2m 28s
Examples (examples/basic)	1m 9s
Examples (examples/graphql_example)	2m 46s
Examples (examples/jsonrpsee_example)	2m 34s
Examples (examples/poem_example)	2m 16s
Examples (examples/proxy_gluesql_example)	1m 25s
Examples (examples/rocket_example)	3m 6s
Examples (examples/salvo_example)	2m 45s
Examples (examples/seaography_example)	2m 55s
Examples (examples/tonic_example)	2m 27s
Compile PostgreSQL (tokio, native-tls)	3m 8s
Compile MySQL (actix, native-tls)	3m 6s
Compile PostgreSQL (tokio, rustls)	3m 11s
Compile SQLite (async-std, native-tls)	3m 11s
Compile MySQL (actix, rustls)	3m 15s
CLI	0s
Compile SQLite (async-std, rustls)	3m 4s
Issues Matrix	0s
Issues	0s
Postgres (14.4, tokio, native-tls)	7m 19s
SQLite (async-std, native-tls)	3m 3s
SQLite (async-std, rustls)	2m 58s
MariaDB (10.6, actix, native-tls)	2m 36s
MySQL (8, actix, native-tls)	3m 41s
MySQL (5.7, actix, native-tls)	3m 49s
	1h 16m 51s

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