Fix ky-universal-polyfill in webpack 5

[timneutkens]

Solves the failing ky-universal suite mentioned here: #15185 (comment)

[Timer]

LGTM

https://github.com/sindresorhus/ky-universal/blob/d1e9a5d8d325542f40ed2d09104aa6ccfc3cd065/package.json#L64-L67

[ijjk]

Stats from current PR

Default Server Mode (Increase detected ⚠️)

General

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
buildDuration	14s	14.1s	⚠️ +98ms
nodeModulesSize	66.5 MB	66.5 MB	✓

Page Load Tests Overall increase ✓

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.592	2.444	-0.15
/ avg req/sec	964.64	1022.89	+58.25
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.944	1.582	-0.36
/error-in-render avg req/sec	1286.29	1580.29	+294

Client Bundles (main, webpack, commons)

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
main-HASH.js gzip	6.72 kB	6.72 kB	✓
webpack-HASH.js gzip	751 B	751 B	✓
19b7e98f51cc..e4c5.js gzip	9.72 kB	9.72 kB	✓
framework.HASH.js gzip	39.1 kB	39.1 kB	✓
Overall change	56.3 kB	56.3 kB	✓

Client Bundles (main, webpack, commons) Modern

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
main-HASH.module.js gzip	5.8 kB	5.8 kB	✓
webpack-HASH..dule.js gzip	751 B	751 B	✓
19b7e98f51cc..dule.js gzip	6.12 kB	6.12 kB	✓
framework.HA..dule.js gzip	39.1 kB	39.1 kB	✓
Overall change	51.8 kB	51.8 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
polyfills-HASH.js gzip	30.8 kB	30.8 kB	✓
Overall change	30.8 kB	30.8 kB	✓

Client Build Manifests

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
_buildManifest.js gzip	267 B	267 B	✓
_buildManife..dule.js gzip	273 B	273 B	✓
Overall change	540 B	540 B	✓

Rendered Page Sizes

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
index.html gzip	954 B	954 B	✓
link.html gzip	961 B	961 B	✓
withRouter.html gzip	947 B	947 B	✓
Overall change	2.86 kB	2.86 kB	✓

---

Serverless Mode

General

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
buildDuration	15s	17s	⚠️ +2s
nodeModulesSize	66.5 MB	66.5 MB	✓

Client Bundles (main, webpack, commons)

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
main-HASH.js gzip	6.72 kB	6.72 kB	✓
webpack-HASH.js gzip	751 B	751 B	✓
19b7e98f51cc..e4c5.js gzip	9.72 kB	9.72 kB	✓
framework.HASH.js gzip	39.1 kB	39.1 kB	✓
Overall change	56.3 kB	56.3 kB	✓

Client Bundles (main, webpack, commons) Modern

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
main-HASH.module.js gzip	5.8 kB	5.8 kB	✓
webpack-HASH..dule.js gzip	751 B	751 B	✓
19b7e98f51cc..dule.js gzip	6.12 kB	6.12 kB	✓
framework.HA..dule.js gzip	39.1 kB	39.1 kB	✓
Overall change	51.8 kB	51.8 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
polyfills-HASH.js gzip	30.8 kB	30.8 kB	✓
Overall change	30.8 kB	30.8 kB	✓

Client Build Manifests

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
_buildManifest.js gzip	267 B	267 B	✓
_buildManife..dule.js gzip	273 B	273 B	✓
Overall change	540 B	540 B	✓

Serverless bundles

	vercel/next.js canary	timneutkens/next.js fix/ky-universal-polyfill	Change
_error.js	882 kB	882 kB	✓
404.html	4.17 kB	4.17 kB	✓
hooks.html	3.79 kB	3.79 kB	✓
index.js	882 kB	882 kB	✓
link.js	923 kB	923 kB	✓
routerDirect.js	917 kB	917 kB	✓
withRouter.js	917 kB	917 kB	✓
Overall change	4.53 MB	4.53 MB	✓

Commit: ac62c20