fix(expect)!: loosen toMatchObject and objectContaining for Proxy.get

[hi-ogawa]

Description

• closes toMatchObject doesn't work well with Proxy objects #6672

I'm not sure if this behavior is the best, but I'm creating a PR to test a few things.
Technically this is a breaking change since people might be using negating expect(someProxy).not.toMatchObject({ ... }) to assert proxy keys not being there.

pros

• convenient for testing Proxy.get
• toMatchObject/objectContaining already allows testing non-enumerable properties (e.g. Error.cause)

cons

• Proxy.get won't give better diff since non-enumerable
• breaking change
• no jest compat

todo

• docs to explain what type of properties (enumerable vs. non-enumerable) are considered for toEqual, toMatchObject, etc... also diff format

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Tests

• Run the tests with pnpm test:ci.

Documentation

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Changesets

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[hi-ogawa]

Closing as par #6672 (comment)