ALIS & SLIS count checks

The checks are implemented as two new Bash operator DAG tasks. Workflow:

• query Hive for a dataset's rows count
• print it to standard output (available in the task's log)
• if a count is zero, return exit code 42 😉 & fail the task without retrying. This will make the whole DAG fail
• send an email alert when either task fails

Bug: T347566 Bug: T347569