chore: using vite for easier dev setup & fix test runner issues

[InfiniteXyy]

This PR contains 3 dev improvements and fixes (Without any code base update)

1. I found that the existing dev server config for is not working for webpack 5. Since the playground is just a simple web project, I repleace webpack with vite to make dev working flow faster and simpler.
2. update CI node version to 16
3. There is something wrong with the Unit test code, the fake timer was inited twice, which will raise an error in newer version of Sinon.
   

   rxjs-hooks/src/__test__/use-observable.spec.tsx

   Line 122 in 29721bf

   const timer = Sinon.useFakeTimers()

[codecov]

Codecov Report

Merging #1019 (a17e604) into master (6045af9) will not change coverage.
The diff coverage is 100.00%.

❗ Current head a17e604 differs from pull request most recent head 0dddab5. Consider uploading reports for the commit 0dddab5 to get more accurate results

@@ Coverage Diff @@ ## master #1019 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 2 2 Lines 51 57 +6 Branches 6 5 -1 ========================================= + Hits 51 57 +6 

Impacted Files	Coverage Δ
src/use-event-callback.ts	100.00% <100.00%> (ø)
src/use-observable.ts	100.00% <100.00%> (ø)

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