Poetry installation with hermit

### Motivation
We use [poetry](https://python-poetry.org/docs/) for running integration tests written in python.
Poetry have to be installed separately and doesn't include in hermit.
Also, it's installation is not trivial and it has to be installed with a specific python version 3.9 (not sure why).
Therefore, its installation repeats more than once in our CI, and developers have to install it manually.

### Definition of done
- [ ] Add poetry to hermit as cloudbeat dependency (not trivial)
- [ ] Remove poetry installation from our testing setup
- [ ] Remove poetry installation documentation

### Out of scope

### Related tasks/epics
Reference related issues and epics