Use console.log in tutorial instead of alert (#3831)

* Updating tutorial to use console.log instead of alert

Chrome is deprecating alerts

* Revert remove space from my auto-linter

Co-authored-by: Bev Lau <bev@fb.com>

Author: bev-a-tron

content/tutorial/tutorial.md

@@ -235,15 +235,15 @@ First, change the button tag that is returned from the Square component's `rende
 class Square extends React.Component {
   render() {
     return (
-      <button className="square" onClick={function() { alert('click'); }}>
+      <button className="square" onClick={function() { console.log('click'); }}>
         {this.props.value}
       </button>
     );
   }
 }
 ```
 
-If you click on a Square now, you should see an alert in your browser.
+If you click on a Square now, you should see 'click' in your browser's devtools console.
 
 >Note
 >
@@ -253,15 +253,15 @@ If you click on a Square now, you should see an alert in your browser.
 >class Square extends React.Component {
 >  render() {
 >    return (
->      <button className="square" onClick={() => alert('click')}>
+>      <button className="square" onClick={() => console.log('click')}>
 >        {this.props.value}
 >      </button>
 >    );
 >  }
 >}
 >```
 >
->Notice how with `onClick={() => alert('click')}`, we're passing *a function* as the `onClick` prop. React will only call this function after a click. Forgetting `() =>` and writing `onClick={alert('click')}` is a common mistake, and would fire the alert every time the component re-renders.
+>Notice how with `onClick={() => console.log('click')}`, we're passing *a function* as the `onClick` prop. React will only call this function after a click. Forgetting `() =>` and writing `onClick={console.log('click')}` is a common mistake, and would fire every time the component re-renders.
 
 As a next step, we want the Square component to "remember" that it got clicked, and fill it with an "X" mark. To "remember" things, components use **state**.
 
@@ -280,7 +280,7 @@ class Square extends React.Component {
 
   render() {
     return (
-      <button className="square" onClick={() => alert('click')}>
+      <button className="square" onClick={() => console.log('click')}>
         {this.props.value}
       </button>
     );