Fix GotoDeclaration in Enum implementing interface

[junichi11]

Example

<?php
namespace Enum1;

interface ExampleInterface1 {}
interface ExampleInterface2 {}

namespace Enum2;

use Enum1\ExampleInterface1;
use Enum1\ExampleInterface2;

enum EnumImpl1 implements ExampleInterface1 {
    case A = 'A';
    case B = 'B';
}

enum EnumImpl2 implements ExampleInterface1, ExampleInterface2 {
    case A = 'A';
    case B = 'B';
}

Before:

After:

[junichi11]

@tmysik Could you please have a look at this? If there is no problem, let's merge it. Thank you!

[tmysik]

Thanks for the tests.