Replace querystring with URLSearchParams

[benmccann]

Describe the bug

The querystring API is considered legacy and it's recommended to use URLSearchParams instead. I'm getting a warning when building the SvelteKit codebase with Rollup and would like to get rid of the warning

Reproduction

vite/packages/vite/src/node/plugins/worker.ts

Line 5 in 0693d03

import qs, { ParsedUrlQuery } from 'querystring'

System Info

Vite `master`

Used Package Manager

pnpm

Logs

default imported from external module 'querystring' but never used

Validations

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