fix: preserve symbols when creating derived rest properties

[Rich-Harris]

fixes #17094

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Playground

pnpm add https://pkg.pr.new/svelte@17096

[7nik]

getOwnPropertySymbols() returns non-enumerable symbol keys as well. REPL

[7nik]

I guess we can do just one loop over Reflect.ownKeys(obj) + check Object.propertyIsEnumerable.call(obj, key)