Move antlr4 to devDependencies in bnf package (#103)

* Initial plan

* Move antlr4 from dependencies to devDependencies in bnf package

Co-authored-by: hzhangxyz <[email protected]>

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Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: hzhangxyz <[email protected]>

Author: Copilot