CSP.LMC fault detection and handling

A detailed analysis of several fault conditions was performed. They are summarized here: https://confluence.skatelescope.org/display/SE/CSP+Fault+Conditions+Analysis Between them 4 fault condition were chosen 1) One or more subsystems not registered within the TANGO DB. 2) Csp Controller TANGO Device server is restarted. 3) A subsystem goes in FAULT during scanning. 4) Command not allowed on a sub-system. Condition 1 and 2 were successfully tested and described in the file: https://gitlab.com/ska-telescope/ska-csp-lmc-mid/-/blob/master/tests/fake-system/features/external_conditions.feature Condition 3 was successfully tested and described in the file: https://gitlab.com/ska-telescope/ska-csp-lmc-mid/-/blob/master/tests/simulated-system/features/processes_execution.feature Condition 4 was successfully tested and described in the file: https://gitlab.com/ska-telescope/ska-csp-lmc-mid/-/blob/master/tests/simulated-system/features/command_execution.feature To perform such tests, a new deployment with simulated subsystems was provided. After a study on testing tools ( https://confluence.skatelescope.org/display/SE/On+some+testing+tools ), TangoSimlib was chosen to develop simulated devices The simulated devices are: controllers for Cbf, Pss and Pst; three subarrays for both Cbf and Pss; three beams for Pst.