Add content to Object.is (#6460)

Added description to Object.is in the JavaScript roadmap before without content.

src/data/roadmaps/javascript/content/objectis@ATma3bLKdmWY_WTsPIKxh.md

@@ -1 +1,21 @@
 # Object.is
+
+The Object.is() static method determines whether two values are the same value.
+
+```js
+console.log(Object.is('1', 1));
+// Expected output: false
+
+console.log(Object.is(NaN, NaN));
+// Expected output: true
+
+console.log(Object.is(-0, 0));
+// Expected output: false
+
+const obj = {};
+console.log(Object.is(obj, {}));
+// Expected output: false
+```
+Visit the following resources to learn more:
+
+- [@article@Object.is() - MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is)