Description
This PR removes the ability to define a custom config file for the queue (when using service()). From now on, configuration will rely exclusively on config('Queue'). If any changes are needed after publishing the config, they can be made manually or through a Registrar.

The queue worker didn’t work with custom config files, and supporting them introduced unnecessary complexity. Sticking to a single config file (similar to how Tasks are handled) offers a cleaner and more predictable approach.

Fixes #57

An alternative PR, which implements custom config file support: #58

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide