Fixed PHP 8.2 deprecation warning: 'creation of dynamic property'.

[hostep]

Fixes deprecation warning with PHP 8.2: Creation of dynamic property xxx is deprecated
I've used old PHP array syntax, just to stay consistent with the rest of the code.

Found with phpstan:

1. Have latest version of phpstan installed somewhere (I've used version 1.10.15)
2. Clone this repo
3. Inside the repo, run:

$ /path/to/phpstan analyse --level=0 . | grep 'Access to an undefined property'

4. Expected to see no errors, but seeing:

  468    Access to an undefined property Zend_Loader_Autoloader_Resource::$_resources.

PR fixes:

• missing member

This fixes one of the warnings mentioned in https://github.com/magento/adobe-commerce-beta/issues/61, If I find more time and this PR actually gets approved, I might try to tackle the others as well one day.