Restore input checked attribute special case

[bqqbarbhg]

Turns out the DOM is annoying and removeAttribute("checked") does remove the checked attribute but HTML latches onto user input state if the checkbox is toggled manually.

Demo in the playground:

export default function StickyCheckbox() {
  const state = useState({ checked: true })
  return <>
      <input type="checkbox" checked={state.checked} />
      <button onClick={() => { state.checked = false; }}>Reset</button>
  </>
}

1. Observe that the reset button works correctly if you don't touch the checkbox
2. Toggle the checkbox manually off/on
3. Observe that the reset button does not work anymore

It's possible that it's required for option selected as well.

[bqqbarbhg]

Hit a somewhat expected snapshot error, but would have expected the snapshot to at least contain checked instead of checked="true"

  ● kaiku › should toggle attributes for certain boolean attributes

    expect(received).toMatchSnapshot()

    Snapshot name: `kaiku should toggle attributes for certain boolean attributes 4`

    Snapshot: "<div><input type=\"text\" disabled=\"true\"><input type=\"checkbox\" checked=\"true\"><select><option selected=\"true\"></option></select></div>"
    Received: "<div><input type=\"text\" disabled=\"true\"><input type=\"checkbox\"><select><option selected=\"true\"></option></select></div>"

[oamaok]

Fixed in c0db6d1