chore: fix dev build replacing undefined (#10740)

Author: sapphi-red

packages/vite/src/node/server/transformRequest.ts

@@ -2,7 +2,7 @@ import { promises as fs } from 'node:fs'
 import path from 'node:path'
 import { performance } from 'node:perf_hooks'
 import getEtag from 'etag'
-import * as convertSourceMap from 'convert-source-map'
+import convertSourceMap from 'convert-source-map'
 import type { SourceDescription, SourceMap } from 'rollup'
 import colors from 'picocolors'
 import type { ViteDevServer } from '..'