message: Remove duplicate make_pair
  Remove duplicate `make_pair`
diff: @@ -58,7 +58,6 @@ namespace eosio { namespace chain {
  using std::make_pair;
  using std::enable_shared_from_this;
  using std::tie;
  - using std::make_pair;
  using std::move;
  using std::forward;
  using std::to_string;
  