Migrate away from gorm, use pgx to query postgres db

[sbchaos]

Description
We are using gorm to query the postgres database, in the current implementation we are facing issues related to high memory consumption which can be due to way be use gorm, as well gorm itself as checked through the benchmarks.

Acceptance Criteria

• Move repositories to use pgx instead of gorm
• Split the stores in groups similar to bounded context

Depends on : 584

Tech Details
Technical details

• Create new persistence models to scan data
• Use explicit queries for the data
• Split the stores in respective groups