Replace custom loader with @node-loaders/tsx

[remcohaszing]

Initial checklist

• [x] I read the support docs
• [x] I read the contributing guide
• [x] I agree to follow the code of conduct
• [x] I searched issues and discussions and couldn’t find anything or linked relevant results below
• [x] I made sure the docs are up to date
• [x] I included tests (or that’s not needed)

Description of changes

We need a loader to load our JSX test file. We currently use a local script, but there are several packages that do this. We don’t need to maintain our own.

This replaces our custom loader with @nodejs-loaders/tsx by the Node.js team.

[remcohaszing]

Apparently this doesn’t work with all Node.js versions we support.

[JounQin]

What's the different with using tsx itself?

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OK, it seems the tsx in @node-loaders/tsx means for .tsx extension, not the tsx npm package...

tsx npm package's name is really confusing.