New Proxmox VE modules to handle pools and their membership (#6604)
* New Proxmox VE modules to handle pools and their membership
* Fix pep8 linting errors
* Fix pep8 and compatibility errors
* Add required fields in the documentation
* Typo fix
* Fix pylint errors
* Fix the last one error
* Address review comments
* Fix linting error
* Add integration tests playbook
* Add assert for the diff mode
* Address review comments
* Fix typo in the word
* Fail for non-empty pool even in check_mode
(cherry picked from commit 16abb96bd8)
Co-authored-by: Sergei Antipov <s.antipov@mulesoft.com>
