Split the GroupColumn Implementations into smaller modules #34756

Job	Run time
Check License Header	2m 18s
cargo check	7m 35s
build with wasm-pack	2m 45s
cargo test (win64)	1h 9m 52s
Check cargo fmt	49s
cargo test (macos)	12m 6s
cargo test (macos-aarch64)	12m 11s
Verify MSRV (Min Supported Rust Version)	9m 10s
Verify Vendored Code	47s
cargo test (amd64)	11m 37s
cargo test datafusion-cli (amd64)	4m 4s
cargo doc	4m 15s
cargo test doc (amd64)	16m 36s
cargo examples (amd64)	13m 49s
check Cargo.toml formatting	3m 3s
clippy	5m 51s
check configs.md and ***_functions.md is up-to-date	3m 10s
cargo test hash collisions (amd64)	17m 22s
Run sqllogictest with Postgres runner	3m 52s
cargo test pyarrow (amd64)	3m 1s
verify benchmark results (amd64)	12m 45s
	3h 36m 58s

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