Issue #4: checkForOkResponse() can't use ZEROCOPY if the String is passed by reference, and it's now. I believe this is a nicer pattern to improve mem usage

Author: gerasdf

src/UniversalTelegramBot.cpp

@@ -758,7 +758,7 @@ String UniversalTelegramBot::sendPhoto(String chat_id, String photo,
   return sendPostPhoto(payload.as<JsonObject>());
 }
 
-bool UniversalTelegramBot::checkForOkResponse(String response) {
+bool UniversalTelegramBot::checkForOkResponse(String &response) {
   int last_id;
   DynamicJsonDocument doc(response.length());
   deserializeJson(doc, response);

src/UniversalTelegramBot.h

@@ -104,7 +104,7 @@ class UniversalTelegramBot {
   bool setMyCommands(const String& commandArray);
 
   int getUpdates(long offset);
-  bool checkForOkResponse(String response);
+  bool checkForOkResponse(String &response);
   telegramMessage messages[HANDLE_MESSAGES];
   long last_message_received;
   String name;