update JSDocs

src/Umbraco.Web.UI.Client/src/libs/observable-api/utils/push-at-to-unique-array.function.ts

@@ -5,6 +5,7 @@
  * @param {T} entry - The object to insert or replace with.
  * @param {getUniqueMethod: (entry: T) => unknown} [getUniqueMethod] - Method to get the unique value of an entry.
  * @description - Append or replaces an item of an Array.
+ * @returns {T[]} - Returns a new array with the updated entry.
  * @example <caption>Example append new entry for a Array. Where the key is unique and the item will be updated if matched with existing.</caption>
  * const entry = {key: 'myKey', value: 'myValue'};
  * const newDataSet = pushToUniqueArray([], entry, x => x.key === key, 1);