[core] Add comment about Object.js

Complement a bit #42571

Author: oliviertassinari

packages/mui-utils/src/useControlled/useControlled.js

@@ -29,6 +29,8 @@ export default function useControlled({ controlled, default: defaultProp, name,
     const { current: defaultValue } = React.useRef(defaultProp);
 
     React.useEffect(() => {
+      // Object.is() is not equivalent to the === operator.
+      // See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is for more details.
       if (!isControlled && !Object.is(defaultValue, defaultProp)) {
         console.error(
           [