JUnit5 docs
AssertJ docs
https://velog.io/@yoondgu/JUnit5-AssertJ-%EA%B0%9C%EC%9A%94-%EB%B0%8F-%EC%82%AC%EC%9A%A9%EB%B2%95
https://velog.io/@woonyumnyum/%EC%9A%B0%EC%BD%94%ED%85%8C-JUnit-5%EC%99%80-AssertJ%EB%A1%9C-%ED%85%8C%EC%8A%A4%ED%8A%B8%EC%BD%94%EB%93%9C-%EC%9E%91%EC%84%B1%ED%95%98%EA%B8%B0
https://velog.io/@dgh06175/Java-JUnit5-%EA%B3%BC-AssertJ-%EB%A1%9C-%EB%8B%A8%EC%9C%84-%ED%85%8C%EC%8A%A4%ED%8A%B8-%EC%9E%91%EC%84%B1%ED%95%98%EA%B8%B0
https://velog.io/@tco0427/%EC%9A%B0%EC%95%84%ED%95%9C-%ED%85%8C%ED%81%AC-%EC%BD%94%EC%8A%A4-3%EC%A3%BC%EC%B0%A8-%EC%A0%95%EB%A6%AC
gradle 오류 해결