fix: handle cloning proxied classes w/ enumerable getters

[tgriesser]

Fixes a very, very edge case I ran into with Vitest's clone, where a class is proxied in a way that exposes its getters as enumerable properties.

const dataSym = Symbol.for('MyClass.data')

class MyClass {
  constructor(obj) {
    this[dataSym] = obj
    return new Proxy(this, {
      ownKeys() {
        return Reflect.ownKeys(obj);
      },
      getOwnPropertyDescriptor(target, p) {
        return {
          ...Reflect.getOwnPropertyDescriptor(obj, p),
          enumerable: true,
        };
      }
    });
  }
  
  get a() {
    return this[dataSym].a
  }
  
  get b() {
    return this[dataSym].b    
  }
}

deepClone(new MyClass({a: 1, b: 2}))

Previously:

TypeError: Cannot set property a of #<MyClass> which has only a getter

New Behavior: clones properly

[sheremet-va]

This will fail if descriptor has only a getter:

Object.defineProperty(objB, 'getter', {
  configurable: true,     
  enumerable: false,
  get: () => 1,
})

[tgriesser]

@sheremet-va updated to handle this case