Provide a single command for complete Power Cycle

[macpijan]

Keyword such as: https://github.com/Dasharo/open-source-firmware-validation/pull/544/files#diff-7cc559f08bc6aab97ac048f606fb57988ff32c55e005a4aaac531bebb8d78860R12 in the tests environment should not be needed.

We should have a single comand in the CLI tool that would make the platform Power On, abstracting away any details - whether it uses Sonoff, or RTE, or both, should not matter.

This would allow us for having a single Power On keyword in test environment for most (all?) platforms.