code: public function set($key, $value)
      {
          Arr::set($this->configs, $key, $value);
  
          return $this;
      }
docs: Set an array item to a given value using "dot" notation.
  
  If no key is given to the method, the entire array will be replaced.
  
  @param  string  $key
  @param  mixed   $value
  @return array