Use timeing-safe password comparison

AI-assistant: Copilot v1.0.7 (Claude Opus 4.6)

Signed-off-by: Pablo Zmdl <pablo@nextcloud.com>

php/src/Data/ConfigurationManager.php

@@ -657,7 +657,7 @@ class ConfigurationManager
             throw new InvalidSettingConfigurationException("Please enter your current password.");
         }
 
-        if ($currentPassword !== $this->password) {
+        if (!hash_equals($this->password, $currentPassword)) {
             throw new InvalidSettingConfigurationException("The entered current password is not correct.");
         }