Using style file makes hmr fail

🐛 bug report

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  adheres to.
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Description of the problem

Using less file make hmr fail

How has this issue affected you? What are you trying to accomplish?

Using less file make hmr fail. And when I just change the text in the index.js, it stills refresh the page.

When I delete one line code in the inset-css.ts, hmr works well although the less file is still in the code.（in my self-host sandpack ）

https://github.com/codesandbox/codesandbox-client/blob/master/packages/app/src/sandbox/eval/transpilers/style/utils/insert-css.ts

To Reproduce

https://codesandbox.io/s/sweet-joana-ge6tc

Your Environment

Start with packages/app/src/sandbox/eval/transpilers/style/utils/insert-css.ts and reproduce the behavior in the linked CodeSandbox example. Compare HMR behavior when the Less file is present with the reported change to index.js. Done means edits update without a full page refresh and HMR still works with the style file included.