title: Error: "category" is not a registered scale
body: <p>I'm trying to migrate Chart.js from <code>2.9.3</code> to <code>3.3.0</code> and even after applying the the changes (<a href="https://www.chartjs.org/docs/latest/getting-started/v3-migration.html" rel="noreferrer">https://www.chartjs.org/docs/latest/getting-started/v3-migration.html</a>) I'm still getting the error:</p>
  <p><code>Error: &quot;category&quot; is not a registered scale</code>.</p>
  <p>This is what I have</p>
  <pre><code>Chart.register(BarController, DoughnutController, LineController, PieController);
  </code></pre>
  <pre><code>new Chart(this.id, {
      type: 'bar',
      data,
      options: {
          responsive: true,
          maintainAspectRatio: false,
          plugins: {
          title: {
              display: options.plugins.title ? true : false,
          },        
          tooltip: {
              mode: 'index',
              intersect: false
          },        
          scales: {
          x: {
              stacked: true,
              gridLines: {
              drawBorder: false,
              display: false,
              },
              ticks: {
              autoSkip: true,
              maxTicksLimit: 13,
              },
          },
          y: {
              stacked: true,
              gridLines: {
              color: '#e6e6e6',
              drawBorder: false,
              },
          }
      }
  });
  </code></pre>
  <p>What could I be missing here?</p>