[FIX] reactivity: don't react when we set the same object

The purpose of this commit is to not notify reactivity when an object is
replaced by the same object (same reference) in an reactive object.

tests/reactivity.test.ts

@@ -993,32 +993,33 @@ describe("Reactivity", () => {
     const obj2 = createReactive({ b: {} }, () => n2++);
     const obj3 = createReactive({ c: {} }, () => n3++);
 
+    // assign the same object should'nt notify reactivity
     obj2.b = obj2.b;
     obj2.b;
     obj3.c = obj3.c;
     obj3.c;
     expect(n1).toBe(0);
-    expect(n2).toBe(1);
-    expect(n3).toBe(1);
+    expect(n2).toBe(0);
+    expect(n3).toBe(0);
 
     obj2.b = obj1;
     obj2.b;
     obj3.c = obj1;
     obj3.c;
     expect(n1).toBe(0);
-    expect(n2).toBe(2);
-    expect(n3).toBe(2);
+    expect(n2).toBe(1);
+    expect(n3).toBe(1);
 
     obj1.a = obj1.a + 2;
     obj1.a;
     expect(n1).toBe(1);
-    expect(n2).toBe(2);
-    expect(n3).toBe(2);
+    expect(n2).toBe(1);
+    expect(n3).toBe(1);
 
     obj2.b.a = obj2.b.a + 1;
     expect(n1).toBe(2);
-    expect(n2).toBe(3);
-    expect(n3).toBe(2);
+    expect(n2).toBe(2);
+    expect(n3).toBe(1);
   });
 
   test("reactive inside other: reading the inner reactive from outer doesn't affect the inner's subscriptions", async () => {