Improve MVP fixtures for managing and observing device states for testing

Ease the testing of the telescope by providing test fixtures that makes it easy to move the telescope devices into a defined state prior to running tests.

Ease testing by provisioning fixtures to make the allocation of dishes to subarrays and executing scans easier.

• skallop linting, test coverage, documentation improved.
• skallop implementation maps to ADR-31 if decided by end of Sprint 10.2 (otherwise implementation matches skampi at the time). 
• A Taranta dashboard shows the states of devices (and their relationships) in the telescope, at a level useful for the telescop- and subarray-level fixtures.

Overall quality (lint warnings, errors, test coverage) and usability (documentation, dashboard) of ska-testing-runway is improved.
Link to Taranta dashboard (now available under KAROO user in Integration): https://jira.skatelescope.org/secure/attachment/19280/202%20-%20version%201.wj