fix: multidimensional array params

[regular-alves]

I found some errors in rendering multidimensional array params such as "param[with][array][]".
When I've tried to execute the command PHP artisan apidoc the following is shown:

ErrorException  : Array to string conversion (View: /path/to/application/vendor/mpociot/laravel-apidoc-generator/resources/views/partials/example-requests/php.blade.php) (View: /path/to/application/vendor/mpociot/laravel-apidoc-generator/resources/views/partials/example-requests/php.blade.php)
  at /path/to/application/vendor/mpociot/laravel-apidoc-generator/src/Tools/Utils.php:166
    162|                 } else {
    163|                     // Hash query param (eg filter[name]=john should become "filter[name]": "john")
    164|                     foreach ($value as $item => $itemValue) {
    165|                         $output .= str_repeat(" ", $spacesIndentation);
  > 166|                         $output .= "$quote$parameter" . "[$item]$quote$delimiter $quote$itemValue$quote,\n";
    167|                     }
    168|                 }
    169|             }
    170|         }
  Exception trace:
  1   Illuminate\View\Engines\CompilerEngine::handleViewException()
      /path/to/application/vendor/laravel/framework/src/Illuminate/View/Engines/PhpEngine.php:45
  2   Mpociot\ApiDoc\Writing\Writer::Mpociot\ApiDoc\Writing\{closure}()
      [internal]:0