fix: finish editing when type enter from last cell when using moveDirectionOnEnter

[jajugoguma]

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• It's submitted to right branch according to our branching model
• It's right issue type on title
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Description

Fixed an issue where typing Enter in the last cell (when there are no more cells to move) would not complete the edit when using the moveDirectionOnEnter option.

As-Is

To-Be

Fixed an issue where typing Enter in the last cell (when there are no more cells to move) would not complete the edit when using the moveDirectionOnEnter option.

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Thank you for your contribution to TOAST UI product. 🎉 😘 ✨

[jwlee1108]

리뷰 완료합니다. 잘 동작하네요.

[sunyoungBae]

리뷰 완료합니다. 고생하셨습니다!