Fix `StorableVariable` `getName` handling for ReflectionUnionType

[rodber]

                ? ($namedType->getName() . ' ') : '';

Error thrown in /var/www/html/app/vendor/chevere/var-support/src/StorableVariable.php:95

# Message
Call to undefined method ReflectionUnionType::getName()

# URI
/

# Method
GET

# Time
2024-08-28T15:45:30+00:00 [1724859930]

# Incident 1_66cf461a3d475

# Backtrace
------------------------------------------------------------
0 /var/www/html/app/vendor/chevere/var-support/src/StorableVariable.php:95
{main}()