Rust

Update datafusion/functions/src/string/concat_ws.rs #61

Job	Run time
linux build test	3m 58s
Check cargo fmt	38s
Check License Header	2m 25s
build with wasm-pack	3m 18s
cargo test (macos-aarch64)	12m 47s
Verify MSRV (Min Supported Rust Version)	9m 31s
Verify Vendored Code	52s
cargo check no default features	7m 59s
cargo check datafusion	4m 45s
cargo check functions	1m 37s
cargo doc	4m 35s
cargo test (amd64)	11m 15s
cargo test datafusion-cli (amd64)	4m 42s
cargo test doc (amd64)	17m 22s
cargo examples (amd64)	14m 15s
verify benchmark results (amd64)	7m 54s
check Cargo.toml formatting	2m 54s
clippy	7m 18s
check configs.md and ***_functions.md is up-to-date	3m 44s
cargo test hash collisions (amd64)	15m 47s
Run sqllogictest with Postgres runner	4m 21s
cargo test pyarrow (amd64)	2m 58s
	2h 24m 55s

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