Add grey as marked font color

Author: Dominik Grenz

personalization-webcomponents/src/components/checklistitem-listitem.vue

@@ -5,7 +5,7 @@
       :checked="!!checklistItem.checked"
     >
     </checklist-checked-circle>
-    <div class="item-title">
+    <div class="item-title" :class="{ 'item-title-checked': checklistItem.checked }">
       {{ checklistItem.title }}
     </div>
   </div>
@@ -26,4 +26,7 @@ defineProps<{
   font-family: "Open Sans", "sans-serif";
   font-size: 18px;
 }
+.item-title-checked {
+  color: #7A8D9F;
+}
 </style>