Fix: allow array spread for prefer-object-spread rule (fixes #10344)

[g-plane]

What is the purpose of this pull request? (put an "X" next to item)

[ ] Documentation update
[x] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[ ] Add autofixing to a rule
[ ] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

#10344

What changes did you make? (Give an overview)
Allow, eg:

Object.assign({}, ...objects)

Is there anything you'd like reviewers to focus on?

[ljharb]

LGTM, but is it possible to make Object.assign({}, foo, ...bar, {}, baz) warn and autofix to Object.assign({ ...foo }, ...bar, { ...baz })?

[platinumazure]

@ljharb That almost seems like a separate change to me. Seems that we could generalize that any variables which follow object literals in an Object.assign call should be turned into object spread (if the entire Object.assign call is not transformed itself). e.g., Object.assign({}, foo) could theoretically be Object.assign({ ...foo }) if we then didn't want to optimize to { ...foo }.

Personally, I think that should be regarded as an enhancement request. This bugfix should just be about allowing Object.assign({}, ...foo).

Let me know if you strongly disagree.

[platinumazure]

LGTM, thanks for contributing!

[ljharb]

(This will likely collide with #10351, but if this is merged ASAP then rebasing that one shouldn't be too tricky)

[mysticatea]

LGTM, thank you.