[net] Add addpeeraddress RPC method

Allows addresses to be added to Address Manager for testing.

src/rpc/client.cpp

@@ -173,6 +173,7 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "createwallet", 4, "avoid_reuse"},
     { "createwallet", 5, "descriptors"},
     { "getnodeaddresses", 0, "count"},
+    { "addpeeraddress", 1, "port"},
     { "stop", 0, "wait" },
 };
 // clang-format on