[fix] handle AssignmentPattern with ObjectPattern in rewrite_identifier

[Shinyaigeek]

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Tests

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Motivation

fix #6699

Hi team!
There is a lack of consideration in handling export props with destructure assignment.
In transforming the left of destructure assignment with AssignmentPattern (such as let { bar = "hoge" } in let { bar = "hoge" } = {}) , compiler handle only the case declaration's type is Identifier, but declaration's type in destructuring assignment with AssignmentPattern could be ObjectPattern, RestElement, ArrayPattern, AssignmentPattern. This lack of consideration caused #6699 error because such a pattern was handled as Identifier.

I fixed it (and add the test about it).