Optimzing Search on Foreign Keys

[king-11]

The problem associated with a search on foreign keys is related to the N+1 problem where more than required times the Database is hit, which we can reduce by using select_related and prefetch_related for one to many and many to many keys where joins would allow DB to be hit only once rather than multiple times reducing the querying time.

InstiApp/lite-hai-backend#80 and InstiApp/lite-hai-backend#82 can be taken as a reference for this