Ignore a lower bound that refers to the inferred template argument itself

[HawkForge]

Closes phpstan/phpstan#15434

Since 2.3.0, passing an object whose template argument is still being inferred to its own method makes the argument refer to itself:

/** @template TOwner of object */
class WeakAnalysingMap
{
	/** @param TOwner $owner */
	public function set(object $owner): void {}
}

$map = new WeakAnalysingMap(); // WeakAnalysingMap<WeakAnalysingMap<object>>, 2.2.17: WeakAnalysingMap<object>
$map->set($map); // Parameter #1 $owner of method WeakAnalysingMap<WeakAnalysingMap<object>>::set() expects WeakAnalysingMap<object>, WeakAnalysingMap<WeakAnalysingMap<object>> given.

$map->set($map) records WeakAnalysingMap<TOwner> as a lower bound on the new site's own TOwner. When TemplateArgumentSolver resolves that bound, the inner TOwner is the site that is being resolved, so resolveKey() returns its delegate (object). The site then resolves to WeakAnalysingMap<object>, and $map no longer matches the parameter it was inferred from.

A lower bound that contains the argument it bounds carries no information about it. resolveObservation() now skips such bounds, so the argument falls back to its bound (object), as on 2.2.17. Bounds from other calls still count: $map->set(new stdClass()) still infers WeakAnalysingMap<stdClass>.

• tests/PHPStan/Rules/Methods/data/bug-15434.php is the issue's code. The test fails without the change in TemplateArgumentSolver.php (it reports the argument.type error from the issue) and passes with it.
• TemplateArgumentSolver has no turbo mirror, so turbo-ext/ is unchanged.
• make tests passes, and phpcs is clean on the changed files.