Use the same error message for different kind of authentiction errors (#13306)

This prevents usernames to be guess as the application confirms or denies their existence.

LibreNMS/Authentication/MysqlAuthorizer.php

@@ -23,7 +23,7 @@ class MysqlAuthorizer extends AuthorizerBase
         $enabled = $user_data->enabled;
 
         if (! $enabled) {
-            throw new AuthenticationException($message = 'login denied');
+            throw new AuthenticationException();
         }
 
         if (Hash::check($password, $hash)) {

app/Providers/LegacyUserProvider.php

@@ -128,7 +128,7 @@ class LegacyUserProvider implements UserProvider
             }
 
             if (empty($credentials['username']) || ! $authorizer->authenticate($credentials)) {
-                throw new AuthenticationException('Invalid Credentials');
+                throw new AuthenticationException();
             }
 
             return true;