TSInterfaceDeclaration compatibility with oxc parser

[LukasBombach]

When printing a TypeScript interface parsed with Oxc, esrap will add a random extends keyword and create a syntax error

interface Props {
  value?: string;
  className?: string;
}

// becomes

interface Props extends { value?: string; className?: string }
//                    ^^^
//                       syntax error  

This is because Oxc parser creates a slightly different AST for TSInterfaceDeclarations from what esrap expects. When parsing this interface with Acorn, it will create an AST node like this

{
  "type": "TSInterfaceDeclaration",
  "id": { /* snip */ },
  "body": { /* snip */ },
}

the interface does not extend any other interface so there is no extends property in the AST. Oxc will create an empty array here

{
  "type": "TSInterfaceDeclaration",
  "id": { /* snip */ },
  "body": { /* snip */ },
  "extends": [],
}

This PR fixes that, by adding a check for an empty array on the extends property.

[changeset-bot]

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Latest commit: f8132c6

The changes in this PR will be included in the next version bump.

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esrap	Patch

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[LukasBombach]

Hey folks, I'd love to write a test for this, but there is no setup another parser than Acorn. If there is any direction I can take here, I'd happily go there if you have any suggestions

[jycouet]

It's actually already done in this PR: https://github.com/sveltejs/esrap/pull/70/files#diff-7c3ad21f697e100eaf9b40c3c6e608b0bf6fdd7d66714fdd322df0853b3be8c6R1948

With a setup to have tests with oxc-parser

I'll have a look at the other PR to see what needs to be done to move foward.

Thank you for your push 💪