adding cvd risk score to reporting_patient_prescriptions (#5785)

**Story card:**
[SIMPLEBACK-94](https://rtsl.atlassian.net/browse/SIMPLEBACK-94)

## Because

We needed cvd risk score added to the reporting_patient_prescriptions
table which is needed for the statin report to run faster.

## This addresses

Adding latest lower and upper range to the
reporting_patient_prescriptions table.
Adding index on month_date and patient_id to make the merge join faster.
Data can be populated for the newly added columns asynchronously using
full_partitioned_refresh task

## Test instructions

N/A

---------

Co-authored-by: Ayushi Agrawal <ayushiagrawal@RTSL-P172G93770.local>

Author: aagrawalrtsl