fix(tablistvertical): no longer require aria-label (#18571)

Author: ariellalgilmore

packages/react/__tests__/__snapshots__/PublicAPI-test.js.snap

@@ -7889,7 +7889,6 @@ Map {
         "type": "oneOf",
       },
       "aria-label": Object {
-        "isRequired": true,
         "type": "string",
       },
       "children": Object {

packages/react/src/components/Tabs/Tabs.tsx

@@ -854,7 +854,7 @@ export interface TabListVerticalProps extends DivAttributes {
    * Provide an accessible label to be read when a user interacts with this
    * component
    */
-  'aria-label': string;
+  'aria-label'?: string;
 
   /**
    * Provide child elements to be rendered inside `ContentTabs`.
@@ -1068,7 +1068,7 @@ TabListVertical.propTypes = {
    * Provide an accessible label to be read when a user interacts with this
    * component
    */
-  'aria-label': PropTypes.string.isRequired,
+  'aria-label': PropTypes.string,
 
   /**
    * Provide child elements to be rendered inside `ContentTabs`.