HDS-5289 Add title to donut chart example

Author: KristinLBradley

packages/components/src/components/hds/charts/donut/options.js

@@ -1,5 +1,5 @@
 export default {
-  title: ' ', // Set title using @title on the component
+  title: '', // Set title using @title on the component
   resizable: true,
   legend: {
     // alignment: 'left', // = alignment w/i container, options: 'left', 'right', 'center'

showcase/app/templates/page-components/charts/index.hbs

@@ -13,7 +13,7 @@
   <Hds::Layout::Grid @columnWidth="33.33%" @gap="12">
     <Hds::Card::Container @hasBorder={{true}} {{style padding="1.5rem"}}>
       <Hds::Text::Display @size="300">Clusters</Hds::Text::Display>
-      <Hds::Charts::Donut @data={{this.model.DONUT_CLUSTERS_DATA}} />
+      <Hds::Charts::Donut @data={{this.model.DONUT_CLUSTERS_DATA}} @title="Cluster types" />
     </Hds::Card::Container>
 
     <Hds::Card::Container @hasBorder={{true}} {{style padding="1.5rem"}}>