… error page (lyrixx)

This PR was squashed before being merged into the 6.3 branch.

Discussion
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[ErrorHander] Display exception properties in the HTML error page

| Q             | A
| ------------- | ---
| Branch?       | 6.3
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | Fix #49613
| License       | MIT
| Doc PR        |

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![image](https://user-images.githubusercontent.com/408368/223196868-77cd3215-7b40-4fab-8aa5-0327d39b5ef6.png)

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<details>

<summary>Code to reproduce</summary>

```php

class MyException extends \Exception
{
    public function __construct()
    {
        parent ::__construct('some_message', 0, new MyException2());
    }

    public string $myMessage = 'some_message';
    public string $myCode = 'some_code';
    private string $privateStuff = 'private_stuff';
}

class MyException2 extends \Exception
{
    private string $anotherPrivateStuff = 'another_private_stuff';
}
```

</details>

Commits
-------

b041d06 [ErrorHander] Display exception properties in the HTML error page