get timestamp of prev. run()

This function returns the time of the last run (not test) of the profile (i.e. not the current run). Example: "2021-09-22 10:39:18.0".

The returned value is based on the logs in the Control Center under "Logs/Overview". If no log entry is found there for this profile, the return value of the function is "1970-01-01 00:00:00.0".