Internship assigment done

[chaudharykapil]

• [x] Get the test coverage to 95%
• [x] All tests has been passed
• [x] Add all missing APIs mentioned in Assigment and get the automated tests to pass
• [x] Add all SQL tests present inside tests/SQL/ and passed
• [x] Add tests for grading API
• [x] Dockerize your application by creating a Dockerfile and a docker-compose.yml file.