QAN is not showing the Query with Errors in Profile section

Impact on the user:

• User is not able to see Queries with Errors in the Profile section. Thim makes an almost useless feature to track queries with errors

Steps to reproduce:

1. Data source?
2. Set up PMM
3. go to Mysql
4. execute some queries with error, for example, "Select * from UNEXISTED_DB "
5. Add "Queries with errors" column in QAN

Actual result:

• the value in all rows will be N/A , even for the presently added queries with error

Expected Result:

• Query with error presented and in Profile it shows real numbers, not N/a

Workaround:
N/A

Suggested implementation: 

Add num_queries_with_errors field to query profile

https://github.com/percona/qan-api2/blob/598736b896aaa60c5e7acfcdf02867bc894416a4/models/reporter.go#L50

Details