Fix params.size() check in "protx list wallet" RPC (#3259)

This should have been "> 4" as otherwise it bails out when the height is
specified.

src/rpc/rpcevo.cpp

@@ -974,7 +974,7 @@ UniValue protx_list(const JSONRPCRequest& request)
 #ifdef ENABLE_WALLET
         LOCK2(cs_main, pwallet->cs_wallet);
 
-        if (request.params.size() > 3) {
+        if (request.params.size() > 4) {
             protx_list_help();
         }