[CDX-281] Mark itemName as optional in trackSearchResultClick (#444)

* [CDX-281] Mark itemName as optional in trackSearchResultClick

* Update jsdoc

---------

Co-authored-by: Enes Kutay SEZEN <eneskutaysezen@gmail.com>

Author: quiteeasy

src/modules/tracker.js

@@ -908,7 +908,7 @@ class Tracker {
    * @function trackSearchResultClick
    * @param {string} term - Search results query term
    * @param {object} parameters - Additional parameters to be sent with request
-   * @param {string} parameters.itemName - Product item name
+   * @param {string} [parameters.itemName] - Product item name
    * @param {string} parameters.itemId - Product item unique identifier
    * @param {string} [parameters.variationId] - Product item variation unique identifier
    * @param {string} [parameters.resultId] - Search result identifier (returned in response from Constructor)

src/types/tracker.d.ts

@@ -94,7 +94,7 @@ declare class Tracker {
   trackSearchResultClick(
     term: string,
     parameters: {
-      itemName: string;
+      itemName?: string;
       itemId: string;
       variationId?: string;
       resultId?: string;