message: add esp32 persistent test support
  persistent support was added via a PR, but not very well, it is buggy.
diff: @@ -2266,19 +2266,21 @@ String WiFiManager::getModeString(uint8_t mode){
  // set mode ignores WiFi.persistent
  bool WiFiManager::WiFi_Mode(WiFiMode_t m,bool persistent) {
  + bool ret;
  #ifdef ESP8266
  if((wifi_get_opmode() == (uint8) m ) && !persistent) {
  return true;
  }
  - bool ret;
  ETS_UART_INTR_DISABLE();
  if(persistent) ret = wifi_set_opmode(m);
  else ret = wifi_set_opmode_current(m);
  ETS_UART_INTR_ENABLE();
  -
  return ret;
  #elif defined(ESP32)
  - return WiFi.mode(m); // @todo persistent not implemented?
  + if(persistent && esp32persistent) WiFi.persistent(true);
  + ret = WiFi.mode(m); // @todo persistent check persistant mode , NI
  + if(persistent && esp32persistent) WiFi.persistent(false);
  + return ret;
  #endif
  }
  bool WiFiManager::WiFi_Mode(WiFiMode_t m) {
  @@ -2327,7 +2329,11 @@ bool WiFiManager::WiFi_enableSTA(bool enable,bool persistent) {
  return true;
  }
  #elif defined(ESP32)
  - return WiFi.enableSTA(enable); // @todo handle persistent when it is implemented in platform
  + bool ret;
  + if(persistent && esp32persistent) WiFi.persistent(true);
  + ret = WiFi.enableSTA(enable); // @todo handle persistent when it is implemented in platform
  + if(persistent && esp32persistent) WiFi.persistent(false);
  + return ret;
  #endif
  }
  bool WiFiManager::WiFi_enableSTA(bool enable) {
  