Remove unused variable

src/components/site-header/site-search/site-search.tsx

@@ -37,7 +37,6 @@ export class SiteSearch {
   private searchTitleLabel: string;
   private searchCloseLabel: string;
   private searchToolsLabel: string;
-  private searchPlaceholderLabel: string;
   private searchDescriptionLabel: string;
 
   @State() isSearchPanelOpen: boolean = false;
@@ -61,7 +60,6 @@ export class SiteSearch {
       this.searchTitleLabel = this._searchLabels['search_label'];
       this.searchCloseLabel = this._searchLabels['search_close_label'];
       this.searchToolsLabel = this._searchLabels['search_tools_label'];
-      this.searchPlaceholderLabel = this._searchLabels['search_placeholder'];
       this.searchDescriptionLabel = this._searchLabels['search_description'];
     }
   }