LibJS/Bytecode: Don't clobber dst when assigning from object expression

When compiling code like this:

    x = { foo: x }

We don't want to put a new JS::Object in `x` until *after* we've
evaluated `x` for the `foo` field.

This fixes an issue when loading https://puter.com/ :^)

Userland/Libraries/LibJS/Tests/builtins/Array/array-basic.js

@@ -55,3 +55,11 @@ test("basic functionality", () => {
     expect(a.toString()).toBe("1,20,2,,,3");
     expect(a.getterSetterValue).toBe(20);
 });
+
+test("assigning array expression with destination referenced in array expression", () => {
+    function go(i) {
+        var i = [i];
+        return i;
+    }
+    expect(go("foo")).toEqual(["foo"]);
+});