fix: rabbitmqadmin commands for RabbitMQ 4

Introduce wrapper that uses rabbitmqadmin v1 or v2 based on the RABBITMQADMIN_VERSION enviroment variable and adapt scripts and documentation. Mounted troubleshooting utility function directly into the RabbitMQ pod which codenses the documentation and makes testing easier. Test rabbitmq commands from troubleshooting documentation inside integration test.

This MR is ready to be reviewed, but commit 8ad65008 (misc: fix integrationtest cinder volume workaround) should be merged separately before: !3379 (closed)