Call toArray() on objects only

[alies-dev]

method_exists($value, 'toArray') has 2 arguments, the first one is an object instance or a class name, see https://www.php.net/manual/en/function.method-exists.php

It's possible that developers can store full qualified classname to SrtripeObject meta and thus this line

stripe-php/lib/StripeObject.php

Line 420 in 91e2b80

return method_exists($value, 'toArray') ? $value->toArray() : $value;

will throw a fatal error Call to a member function toArray() on string: https://3v4l.org/2Gh07

[ob-stripe]

Thanks for the patch!