InvalidCast on implicit cast of constant-typed properties to string

[flaviovs]

See https://psalm.dev/r/8518ebc0a4

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/8518ebc0a4

<?php

/** @property Foo::PROP_* $aprop */
class Foo {
    public const PROP_ONE = 1;
    
	public function __get(string $name) { return self::PROP_ONE; }
}

$obj = new Foo();

echo $obj->aprop; // This works.

echo "$obj->aprop"; // ERROR: InvalidCast

echo (string)$obj->aprop; // Same.

Psalm output (using commit d4311e3):

ERROR: InvalidCast - 14:7 - Foo::PROP_* cannot be cast to string

ERROR: InvalidCast - 16:14 - Foo::PROP_* cannot be cast to string