Update default admin credentials

README.md

@@ -33,8 +33,8 @@ A Python web application built with Flask that automatically renames PDF files b
    export CLIENT_SECRET="your-client-secret"
    
    # For admin login
-   export ADMIN_USERNAME="admin"
-   export ADMIN_PASSWORD="your-secure-password"
+   export ADMIN_USERNAME="trbcit"
+   export ADMIN_PASSWORD="atdrmbicn"
    
    # Required
    export SECRET_KEY="your-random-secret-key"