chore(deps): update to vitest v4

[sheremet-va]

Description

Requires: vitest-dev/vitest#8765

[sheremet-va]

This test fails:

vite/playground/ssr-deps/__tests__/ssr-deps.spec.ts

Line 103 in 9c8a780

`Hello World from ${process.env.NODE_ENV}!`,

Test receives 'test' NODE_ENV, but in Vitest 3 it was "development" for some reason. I am not sure why this changed in Vite repo.

I think it might be due to the pool rewrite, the evaluation of process.env happens before the global setup now. This will be fixed in Vitest at vitest-dev/vitest#8769, but it's not crucial for Vite test suite, I think having it in the config is better for visibility.

[sapphi-red]

It seems this log is output. It doesn't reproduce on my machine though.

(node:2764) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 message listeners added to [process]. MaxListeners is 10. Use emitter.setMaxListeners() to increase limit
(Use node --trace-warnings ... to show where the warning was created)

https://github.com/vitejs/vite/actions/runs/18722451249/job/53398327751?pr=20984#step:11:93