Deprecate ConnectionFactory and ConnectionFactory::getConnection()

Problem/Motivation

As of

Steps to reproduce

As of https://www.drupal.org/project/rabbitmq/issues/3419129 📌 Major refactor of ConnectionFactory and RabbitmqServiceProvider Active \Drupal\rabbitmq\ConnectionFactory is deprecated in favour of \Drupal\rabbitmq\Factory\ConnectionFactory.

Proposed resolution

Deprecate the class and ConnectionFactory::getConnection in favour of ConnectionFactory::create().

Remaining tasks

Work completed here: https://git.drupalcode.org/project/rabbitmq/-/merge_requests/44

User interface changes

N/A

API changes

ConnectionFactory::getConnection() deprecated.

Data model changes

N/A