startOfPeriod and endOfPeriod not there exception should be handled properly

To reproduce the exception:

1.Install the module, upload the basic report template available at the github repo- https://github.com/hispindia/dhisreport
2. Go to the reports link and click on the report name to edit the sql and replace it with :
select count(distinct p.person_id)
from person p
inner join obs o on o.person_id = p.person_id
where p.voided = 0 and o.voided = 0
and o.concept_id = 1425
and o.value_numeric = 4
3. Now try to Post/Preview the report from the reports link and give any simple inputs as shown in the image and try preview.
4. This results in an exception as shown below in the images attached as well.

Instead of this unhandled exception, the user should be redirected to the post/preview page with a message mentioning the sql query does not contain startOfPeriod and/or endOfPeriod