Fix ky-universal-polyfill in webpack 5 (#15227)

Co-authored-by: Nkodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
Co-authored-by: NJoe Haddad <joe.haddad@zeit.co>

package.json

@@ -122,6 +122,7 @@
     "tree-kill": "1.2.1",
     "typescript": "3.8.3",
     "wait-port": "0.2.2",
+    "web-streams-polyfill": "2.1.1",
     "webpack-bundle-analyzer": "3.6.1",
     "worker-loader": "2.0.0"
   },

yarn.lock

@@ -16016,6 +16016,11 @@ wcwidth@^1.0.0, wcwidth@^1.0.1:
   dependencies:
     defaults "^1.0.3"
 
+web-streams-polyfill@2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/web-streams-polyfill/-/web-streams-polyfill-2.1.1.tgz#2c82b6193849ccb9efaa267772c28260ef68d6d2"
+  integrity sha512-dlNpL2aab3g8CKfGz6rl8FNmGaRWLLn2g/DtSc9IjB30mEdE6XxzPfPSig5BwGSzI+oLxHyETrQGKjrVVhbLCg==
+
 web-vitals@0.2.1:
   version "0.2.1"
   resolved "https://registry.yarnpkg.com/web-vitals/-/web-vitals-0.2.1.tgz#60782fa690243fe35613759a0c26431f57ba7b2d"