[fix] handle undefined select value with spread

[Shinyaigeek]

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Tests

• Run the tests with npm test and lint the project with npm run lint

Motivation

Fixes #6675

Hi team! <select /> element with bindings props is broken, so I fixed it. This issue is caused by passing undefined spread.value into <select /> value in handling spread props.

I fixed this issue by passing only when spread.value is not undefined as <input /> does.

If something wrong or not enough, please feel free to point out 🙏

[Shinyaigeek]

I don’t know why CI test is failed in npm install without any change in package.json, package-lock.json and workflow file. Does anyone know why?

UPDATE: test seems to be passed, thank you!

[Conduitry]

This looks like a good solution to me, thank you!

The test failure was just a network glitch when Puppeteer was trying to download the Chromium binary, so I manually re-ran the tests.