Update bootstrap.php

[lorro]

Cache::config is deprecated in latest cakePHP versions.
Should be setConfig/getConfig

[botchris]

Hi lorro,

thanks for noticing this and contributing to improve QACMS code.
However, this repo and every core plugin (quickapps-plugins/* at the moment) is maintained using the main repo (quickapps/cms), which is then splitted into different and independent repos like this one (quickapps-plugins/eav). This means that every contribution PR should be sent to the main repo (quickapps/cms), and not directly to plugin-repos.

In the other hand, due con compatibility issues, QACMS's core is fixed to work with CakePHP v3.3.16 at best, CakePHP's getter/setter refactor came in at v3.6 I believe. So this patch won't work with QACMS at this moment.