fix: signup and sign in form

users/templates/librarians/login.html

@@ -17,6 +17,7 @@
     >
       Login
     </button>
+    <p>{{ error_message }}</p>
     <div class="d-flex flex-column align-items-center">
       <p class="my-2">
         Don't have an account? <a href="/auth/sign-up">Sign Up</a>