wallet, rpc: Update migratewallet help text for encrypted wallets

src/wallet/rpc/wallet.cpp

@@ -720,8 +720,8 @@ static RPCHelpMan migratewallet()
         "A new wallet backup will need to be made.\n"
         "\nThe migration process will create a backup of the wallet before migrating. This backup\n"
         "file will be named <wallet name>-<timestamp>.legacy.bak and can be found in the directory\n"
-        "for this wallet. In the event of an incorrect migration, the backup can be restored using restorewallet." +
-        HELP_REQUIRING_PASSPHRASE,
+        "for this wallet. In the event of an incorrect migration, the backup can be restored using restorewallet."
+        "\nEncrypted wallets must have the passphrase provided as an argument to this call.",
         {
             {"wallet_name", RPCArg::Type::STR, RPCArg::DefaultHint{"the wallet name from the RPC endpoint"}, "The name of the wallet to migrate. If provided both here and in the RPC endpoint, the two must be identical."},
             {"passphrase", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "The wallet passphrase"},