A controller parameter without default value creates ReflectionException error

[krishnan57474]

Describe the bug
A controller parameter without default value creates error in routes collector toolbar.

CodeIgniter 4 version
CodeIgniter4 Beta 0.0.2

Affected module(s)
system\Debug\Toolbar\Collectors\Routes.php

Expected behavior, and steps to reproduce if appropriate

1. Set CodeIgniter environment to development
2. Create parameter ( public function index(...$params) ) in index method
3. run

You get

ReflectionException Internal error: Failed to retrieve the default value

The following statement in system\Debug\Toolbar\Collectors\Routes.php:

    '<empty>&nbsp| default: ' . var_export($param->getDefaultValue(), true),

Calling $param->getDefaultValue() without isDefaultValueAvailable check causes this exists error.

Fix

    '<empty>&nbsp| default: ' . var_export($param->isDefaultValueAvailable() ? $param->getDefaultValue() : null, true),