fix wrapping of object with null prototype

[MrFoxPro]

Summary

Could not add object with null prototype to store/mutable
https://playground.solidjs.com/anonymous/90e80787-1a13-41ff-82ea-90c0d1f20a80

Uncaught TypeError: Cannot convert undefined or null to object
    at Function.getOwnPropertyDescriptors (<anonymous>)

How did you test this change?

test("Object.create(null) is allowed", () => {
  const user = createMutable(Object.assign(Object.create(null), { name: "John" }));
  expect(user.name).toBe("John");
});

[changeset-bot]

🦋 Changeset detected

Latest commit: 18d3c81

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
solid-js	Patch
test-integration	Patch

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[coveralls]

Pull Request Test Coverage Report for Build 10999665099

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.004%) to 93.346%

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Totals
Change from base Build 10692001464:	0.004%
Covered Lines:	4197
Relevant Lines:	4430

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💛 - Coveralls