feat: add function to allow order by nulls #4247

Job	Run time
Unit Test	3m 21s
Clippy	1m 11s
Examples (examples/actix_example)	2m 25s
Init	4s
Rustfmt	18s
Examples (examples/axum_example)	2m 28s
Examples (examples/basic)	1m 27s
Examples (examples/graphql_example)	2m 37s
Examples (examples/jsonrpsee_example)	3m 3s
Examples (examples/loco_example)	3m 13s
Examples (examples/poem_example)	2m 26s
Examples (examples/proxy_gluesql_example)	1m 12s
Examples (examples/rocket_example)	3m 4s
Examples (examples/rocket_okapi_example)	3m 11s
Examples (examples/salvo_example)	2m 41s
Examples (examples/seaography_example)	2m 26s
Examples (examples/tonic_example)	2m 26s
Compile PostgreSQL (tokio, native-tls)	3m 5s
Compile SQLite (async-std, native-tls)	3m 3s
Compile PostgreSQL (tokio, rustls)	3m 7s
Compile SQLite (async-std, rustls)	2m 48s
Compile MySQL (actix, native-tls)	2m 43s
CLI	0s
Compile MySQL (actix, rustls)	2m 53s
Issues Matrix	0s
Issues	0s
SQLite (async-std, native-tls)	4m 18s
SQLite (async-std, rustls)	4m 42s
Postgres (14.4, tokio, native-tls)	6m 55s
MariaDB (10.6, actix, native-tls)	2m 17s
MySQL (8, actix, native-tls)	3m 16s
MySQL (5.7, actix, native-tls)	3m 23s
	1h 20m 3s

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