fix: Match PBKDF2 iterations

src/main/java/ru/vidtu/ias/crypt/Crypt.java

@@ -158,7 +158,7 @@ static byte[] pbkdfAesDecrypt(byte[] encrypted, String password, byte[] salt, by
         try {
             // Create the key.
             SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA512");
-            KeySpec spec = new PBEKeySpec(password.toCharArray(), salt, 300_000, 256);
+            KeySpec spec = new PBEKeySpec(password.toCharArray(), salt, 500_000, 256);
             byte[] secret = factory.generateSecret(spec).getEncoded();
             SecretKey key = new SecretKeySpec(secret, "AES");
             Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");