[11.x] Allow the authorize method to accept Backed Enums directly

[johanvanhelden]

This PR improves the authorize method by allowing it to accept Backed Enums directly as the ability parameter.

In most of the applications I am working in, we are using BackedEnums for permissions:

enum DashboardPermission: string
{
    case VIEW = 'dashboard.view';
}

Currently, when performing authorization checks using the authorize method, developers need to explicitly access the value of the enum:

    public function index(): Response
    {
        $this->authorize(DashboardPermission::VIEW->value);

        //
    }

This PR modifies the authorize method to accept Backed Enums directly, so there is no need anymore to access the value property manually. With this change, the authorization check could now be:

    public function index(): Response
    {
        $this->authorize(DashboardPermission::VIEW);

        //
    }

Testing:
A test has been added to FoundationAuthorizesRequestsTraitTest to cover the new behavior.