Rust

Improve documentation about extended tests #38161

Job	Run time
Check cargo fmt	41s
Check License Header	1m 36s
linux build test	1m 27s
build with wasm-pack	1m 27s
cargo test (macos-aarch64)	1m 23s
Verify MSRV (Min Supported Rust Version)	1m 27s
Verify Vendored Code	50s
cargo test (amd64)	1s
cargo check functions	1s
cargo check no default features	1s
cargo check datafusion	1s
check Cargo.toml formatting	1s
clippy	1s
check configs.md and ***_functions.md is up-to-date	1s
cargo doc	1s
cargo test datafusion-cli (amd64)	1s
cargo test doc (amd64)	1s
cargo examples (amd64)	1s
Run sqllogictest with Postgres runner	1s
cargo test pyarrow (amd64)	1s
verify benchmark results (amd64)	1s
	9m 5s

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