Support try_from_array and eq_array for ScalarValue::Union #1312

Job	Run time
cargo check	8m 33s
build with wasm-pack	2m 9s
Check cargo fmt	34s
cargo test (macos)	11m 4s
cargo test (macos-aarch64)	11m 29s
Verify MSRV (Min Supported Rust Version)	4m 14s
Verify Vendored Code	52s
cargo test (win64)	32m 11s
cargo test datafusion-cli (amd64)	3m 50s
cargo test (amd64)	9m 12s
check Cargo.toml formatting	3m 8s
clippy	1m 41s
cargo test hash collisions (amd64)	2m 13s
cargo doc	3m 57s
cargo test doc (amd64)	12m 35s
Run sqllogictest with Postgres runner	3m 9s
verify benchmark results (amd64)	10m 11s
cargo examples (amd64)	11m 42s
cargo test pyarrow (amd64)	3m 0s
check configs.md is up-to-date	2m 29s
	2h 18m 13s

Provide feedback