Moler

Improved
* Check if passed object is ConnectionObserver instance in MolerConnectionForSingleThreadRunner

Added
* add `ADDITIONAL_PARAMS` in device configuration
* add possibility use `single-threaded` runner for all ConnectionObservers

Improved
* Add more readable traceback
* Parsing fail and success for RunScript command
* Add new regex for retry password(ssh/telnet commands)

Improved
* Add logs for troubleshoot threads

Improved
* Set flag to run in embeded command

Added
* Unix command nping
* Unix command sysctl

Improved
* Check cmd status before break
* Commands and events - 100% coverage in tests
* Run tests with flake8


Fixed
* CI on GitHub Actions and resolved issues with new Python
* Fix the possibility to break command if the command is not running

Improved
* goto_state_bg
* Parallel tests for device SM