Add incrementing and decrementing prometheus metric for kie execution errors

The metric kie_server_execution_error_total is used to show execution errors in the Prometheus dashboard and it will not get decreased even if the job is eventually properly executed. The metrics need to show the exact count of  job execution errors.

This requires

• Creating a new Prometheus metric to show the count of execution errors while executing a job.
• Creating a new Prometheus metric to show the count of number of jobs in retrying status.