Don't use optional on crypto randomUuid

The tests fail because of it for some reason:

./node_modules/next/types/index.d.ts:209:5
Type error: Overload signatures must all be optional or required.

  207 |       array: T
  208 |     ): T
> 209 |     randomUUID?(): string
      |     ^
  210 |   }
  211 | }
  212 |

packages/next/types/index.d.ts

@@ -206,7 +206,7 @@ declare global {
     >(
       array: T
     ): T
-    randomUUID?(): string
+    randomUUID(): string
   }
 }