fix(utils): Clone RegExp values with new RegExp instead of `struc…

…turedClone` (fix #19245, fix #18875)

- Jest appears to provide its own global `structuredClone` that modifies
  `RegExp`s in such a way that they fail `instanceof RegExp` checks,
  causing an error in a rollup plugin used by `vite` (and likely elsewhere).
  `new RegExp` seems to correctly clone `RegExp`s in Jest.

packages/vite/src/node/utils.ts

@@ -1093,7 +1093,7 @@ function deepClone<T>(value: T): DeepWritable<T> {
     return value as DeepWritable<T>
   }
   if (value instanceof RegExp) {
-    return structuredClone(value) as DeepWritable<T>
+    return new RegExp(value) as DeepWritable<T>
   }
   if (typeof value === 'object' && value != null) {
     throw new Error('Cannot deep clone non-plain object')