url: set formatUrl method as no side effect

PR-URL: nodejs#46884
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

src/node_url.cc

@@ -313,7 +313,7 @@ void Initialize(Local<Object> target,
                 void* priv) {
   SetMethod(context, target, "parse", Parse);
   SetMethod(context, target, "updateUrl", UpdateUrl);
-  SetMethod(context, target, "formatUrl", FormatUrl);
+  SetMethodNoSideEffect(context, target, "formatUrl", FormatUrl);
 
   SetMethodNoSideEffect(context, target, "domainToASCII", DomainToASCII);
   SetMethodNoSideEffect(context, target, "domainToUnicode", DomainToUnicode);