title: How to change the state correctly? (read-only error)
body: <p>Each click calls the function <code>handleSubmit</code>.<br>
  In the function I have to increase the page number by 1.<br>
  But the console error <strong>Uncaught Error: "page" is read-only</strong><br>
  How to change the state correctly?</p>
  
  <pre><code>const Cards = () =&gt; {
    const [page, setPage] = useState(1);
  
    const handleSubmit = e =&gt; {
      e.preventDefault();
      setPage(page += 1);
      const axios = require('axios');
      const url = '/users'
  
      axios.get(url, {
        params: { page: page }
      }, {headers: {'Content-Type': 'text/javascript'}})
      .then(function (response) {
  
      })
      .catch(function (error) {
        console.log(error);
      })
      .then(function () {
        // always executed
      });
    };
  
    return (
      // ...
    )
  
  };
  
  export default Cards;
  </code></pre>