fix: add install pnpm workflow.

[Brokyeom]

변경사항

• github-action에 기본적으로 설치되어 있지 않던 pnpm 을 설치하는 워크플로 스크립트를 추가합니다.

링크

시급한 정도

🏃‍♂️ 보통 : 최대한 빠르게 리뷰 부탁드립니다.

기타 사항

[height]

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[changeset-bot]

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Latest commit: 25b2679

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