Replace std::to_string with locale-independent alternative

src/bitcoin-tx.cpp

@@ -20,6 +20,7 @@
 #include <util/moneystr.h>
 #include <util/rbf.h>
 #include <util/strencodings.h>
+#include <util/string.h>
 #include <util/system.h>
 #include <util/translation.h>
 
@@ -357,7 +358,7 @@ static void MutateTxAddOutMultiSig(CMutableTransaction& tx, const std::string& s
 
     if (required < 1 || required > MAX_PUBKEYS_PER_MULTISIG || numkeys < 1 || numkeys > MAX_PUBKEYS_PER_MULTISIG || numkeys < required)
         throw std::runtime_error("multisig parameter mismatch. Required " \
-                            + std::to_string(required) + " of " + std::to_string(numkeys) + "signatures.");
+                            + ToString(required) + " of " + ToString(numkeys) + "signatures.");
 
     // extract and validate PUBKEYs
     std::vector<CPubKey> pubkeys;