Merge #18316: util: HelpExampleRpc formatting

a33cffb util: HelpExampleRpc formatting fixup (Jon Atack)

Pull request description:

  Minor visual fixup of the HelpExampleRpc template; conforms to the JSON-RPC spec as per https://www.jsonrpc.org/specification#examples. (I'm... somewhat embarassed to open such a minor change, but this is what is shown in all the CLI/RPC help docs.)

ACKs for top commit:
  laanwj:
    ACK a33cffb

Tree-SHA512: 8f1dee080c224742fff60a33fec6f5fb1d59c9fa51f3f2a67bf2e1837dbfa25f12a69e34518936588940013b0e61f55378b4f1a571c47c3cb081ca5b245e1091

Author: fanquake

src/rpc/util.cpp

@@ -116,8 +116,8 @@ std::string HelpExampleCli(const std::string& methodname, const std::string& arg
 
 std::string HelpExampleRpc(const std::string& methodname, const std::string& args)
 {
-    return "> curl --user myusername --data-binary '{\"jsonrpc\": \"1.0\", \"id\":\"curltest\", "
-        "\"method\": \"" + methodname + "\", \"params\": [" + args + "] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/\n";
+    return "> curl --user myusername --data-binary '{\"jsonrpc\": \"1.0\", \"id\": \"curltest\", "
+        "\"method\": \"" + methodname + "\", \"params\": [" + args + "]}' -H 'content-type: text/plain;' http://127.0.0.1:8332/\n";
 }
 
 // Converts a hex string to a public key if possible