에러기록 - Element type is invalid:

Error: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.
Check the render method of BoardList.

에러발생 : import된 컴포넌트의 경로나 오타발생함

원인 : container페이지에 import default 된 컴포넌트를 {}로 묶어서 import해옴

해결 : {}삭제

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