Fix code scanning alert #3: DOM text reinterpreted as HTML

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

assets/js/admin-pull.js

@@ -39,7 +39,7 @@ if ( chooseConnection && choosePostType && form ) {
 		jQuery( searchBtn ).on( 'click', ( event ) => {
 			event.preventDefault();
 
-			const search = searchField.value;
+			const search = encodeURIComponent(searchField.value);
 
 			document.location = `${ getURL() }&s=${ search }`;