Remove left-over api-utils method (#17595)

Noticed this method was left-over from previous query handling logic in `api-utils` while working on https://github.com/vercel/next.js/pull/17370 so this removes the extra code which should be safe since `api-utils` is an internal file that shouldn't be relied on externally. 

packages/next/next-server/server/api-utils.ts

@@ -162,34 +162,6 @@ function parseJson(str: string): object {
   }
 }
 
-/**
- * Parsing query arguments from request `url` string
- * @param url of request
- * @returns Object with key name of query argument and its value
- */
-export function getQueryParser({ url }: IncomingMessage) {
-  return function parseQuery(): NextApiRequestQuery {
-    const { URL } = require('url')
-    // we provide a placeholder base url because we only want searchParams
-    const params = new URL(url, 'https://n').searchParams
-
-    const query: { [key: string]: string | string[] } = {}
-    for (const [key, value] of params) {
-      if (query[key]) {
-        if (Array.isArray(query[key])) {
-          ;(query[key] as string[]).push(value)
-        } else {
-          query[key] = [query[key], value]
-        }
-      } else {
-        query[key] = value
-      }
-    }
-
-    return query
-  }
-}
-
 /**
  * Parse cookies from `req` header
  * @param req request object