code: public function getSessionKey($jsCode)
      {
          $params = [
              'appid' => $this->config['app_id'],
              'secret' => $this->config['secret'],
              'js_code' => $jsCode,
              'grant_type' => 'authorization_code',
          ];
  
          return $this->parseJSON('GET', [self::JSCODE_TO_SESSION, $params]);
      }
docs: JsCode 2 session key.
  
  @param string $jsCode
  
  @return \EasyWeChat\Support\Collection