Rust

add fast-path for `with_new_children` #49

Job	Run time
Verify Vendored Code	1m 32s
build and run with wasm-pack	5m 12s
Verify MSRV (Min Supported Rust Version)	4m 42s
Check cargo fmt	1m 5s
linux build test	4m 2s
cargo test (macos-aarch64)	11m 13s
cargo check datafusion-substrait features	10m 9s
cargo doc	4m 58s
verify benchmark results (amd64)	10m 45s
cargo check datafusion-functions features	2m 26s
clippy	4m 27s
cargo test (amd64)	11m 15s
check example README is up-to-date	36s
cargo test doc (amd64)	7m 32s
cargo examples (amd64)	10m 37s
cargo test datafusion-cli (amd64)	4m 21s
cargo check datafusion features	11m 40s
cargo check datafusion-common features	2m 5s
Run sqllogictest with Postgres runner	6m 38s
check Cargo.toml formatting	3m 31s
Run sqllogictest in Substrait round-trip mode	6m 57s
check configs.md and ***_functions.md is up-to-date	5m 18s
cargo check datafusion-proto features	4m 48s
	2h 15m 49s

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