[BUG] No validation error messages in the login screen

[annanklv]

Steps to reproduce:

1. Go to https://automationintesting.online/#/admin.
2. Enter invalid credentials or leave the username and password fields empty.
3. Click Login.

Expected result:

There are informative validation error messages of what is wrong.

Examples: For missing credentials: "Username/Password field is required." For invalid credentials: "Invalid username/password."

Actual result:

No validation error messages are shown.