Simplify `EXPR LIKE 'constant'` to `expr = 'constant'` #334

Job	Run time
cargo check	6m 32s
cargo test (macos)	8m 0s
build with wasm-pack	2m 37s
Check cargo fmt	44s
cargo test (macos-aarch64)	11m 9s
Verify MSRV (Min Supported Rust Version)	8m 27s
Verify Vendored Code	50s
cargo test (win64)	1h 0m 27s
cargo test datafusion-cli (amd64)	3m 59s
cargo examples (amd64)	14m 16s
clippy	5m 54s
check Cargo.toml formatting	2m 55s
cargo test hash collisions (amd64)	17m 47s
cargo test (amd64)	12m 25s
cargo doc	4m 57s
check configs.md and ***_functions.md is up-to-date	3m 18s
cargo test doc (amd64)	16m 42s
Run sqllogictest with Postgres runner	3m 48s
cargo test pyarrow (amd64)	2m 53s
verify benchmark results (amd64)	12m 57s
	3h 20m 37s

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