Fix breaking syntax on removing useless one-line return type hint

[nightlinus]

Fixing useless return type hint was breaking php syntax
Example

<?php
declare(strict_types=1);
/**
 * Date: 2/16/2018
 * Time: 1:42 PM
 *
 * @package
 * @author
 */
class TestClass
{

    /** @return string */
    public function test(): string
    {
    }
}

Transformed into

<?php
declare(strict_types=1);
/**
 * Date: 2/16/2018
 * Time: 1:42 PM
 *
 * @package
 */
    public function test(): string
    {
    }
}

Because of error in detecting changeStart offset.

[kukulich]

@nightlinus Could you please change commit message to format `SniffName: What is changed" ? See my commits https://github.com/slevomat/coding-standard/commits/master

[nightlinus]

@nightlinus Could you please change commit message to format `SniffName: What is changed" ? See my commits https://github.com/slevomat/coding-standard/commits/master

yep, done

[nightlinus]

Thank you, amazing speed.