Adding property type
-----
<?php

class A
{

    public $a
    = 1;
}
-----
$stmts[0]->stmts[0]->type = new Node\Identifier('string');
-----
<?php

class A
{

    public string $a
    = 1;
}
-----
<?php

class A
{
    public
        $b;
}
-----
$stmts[0]->stmts[0]->type = new Node\Identifier('int');
-----
<?php

class A
{
    public
        int $b;
}