toggle font awesome icon

1<!-- HTML -->
2    <button class="btn btn-warning">
3      <i id="tgl" class="fas fa-star"></i>
4    </button>
5<!--  -->
6
7<script>
8      $('button').click(function () {
9        $('#tgl').toggleClass('fa-star fa-grin-stars');
10      });  
11</script>