Description

Fix #4934

This basically strips off the import assertion part as Vite already handles it.

It's still a stage 3 feature, but esbuild, rollup, and other tools all already support it. Using import assertions in deps works today.

Additional context

I see some downsides if we don't strip it, and instead let browsers handle natively:

1. Browser support isn't great yet
2. We can't detect if a JSON import is using import assertions or not, so we have to mark it with a query, making the process a bit complex
3. Native JSON import does not support named imports. It might be confusing that it doesn't work by default in Vite.

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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