UMD build get's recognized as ESM by some bundlers such as esbuild/tsup

[segevfiner]

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• Vue Version: 3.3.4
• Vue Select Version: 4.0.0-beta.6

Describe the bug
The umd build gets recognized as ESM by esbuild/tsup because its file extension is .js and the package.json specifies "type": "module" it should have a .cjs extension to be recognized correctly.

Reproduction Link

Steps To Reproduce

1. Build a package using vue-select with tsup for node (SSR) in CJS format.

Expected behavior
It builds correctly, instead, due to incorrectly assuming the UMD build is ESM, the module.exports statement will be left in the bundle and will overwrite the real module.exports.