Remove unbounded_input from FileSinkOptions #21363

Job	Run time
cargo check	2m 52s
build with wasm-pack	1m 58s
Check cargo fmt	41s
cargo test (mac)	17m 20s
Verify MSRV	6m 18s
Verify Vendored Code	48s
cargo test (win64)	29m 23s
cargo test (amd64)	9m 15s
cargo test doc (amd64)	9m 24s
check Cargo.toml formatting	1m 19s
clippy	4m 21s
cargo test hash collisions (amd64)	8m 42s
check configs.md is up-to-date	2m 10s
cargo doc	3m 19s
cargo test datafusion-cli (amd64)	2m 59s
cargo examples (amd64)	6m 17s
Run sqllogictest with Postgres runner	3m 2s
cargo test pyarrow (amd64)	2m 7s
verify benchmark results (amd64)	9m 34s
	2h 1m 49s

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