fix: update header

Signed-off-by: Abhijeet <abhijeetsaharan2236@gmail.com>

Author: Abhijeet2409

application/frontend/src/scaffolding/Header/Header.tsx

@@ -137,6 +137,7 @@ export const Header = ({ capabilities }: HeaderProps) => {
       <div className={`navbar__mobile-menu ${isMobileMenuOpen ? 'is-open' : ''}`}>
         <button className="mobile-menu-close" onClick={closeMobileMenu}>
            <X size={24} />
+           <span className="sr-only">Close menu</span>
         </button>
         <div className="mobile-search-container">
           <SearchBar />