Zabbix

.......... [DEV-1662] refactored data generation for Update scenario of testDashboardProblemsBySeverityWidget autotest

* commit '665e775c8090c8da15bd00f7d7c4e98ea0cbae7d':
  .......... [DEV-1662] fixes as per review comments
  .......... [DEV-1662] made the data set for the update scenario more compact
  .......... [DEV-1662] fixed error handling for execution via on-before annotation
  .......... [DEV-1662] removed unnecessary widget from data_test.sql
  .......... [DEV-1662] substituted backup of widget table for each Update scenario with a single creation of a separate dashboard

(cherry picked from commit cd09604ae914ef133f0d9bfe5d796b48c4d49819)