Migrate the database manager class from asyncpg/psycopg2 to sqlalchemy

- [ ] ~Define tables using sqlalchemy provided [Table](https://docs.sqlalchemy.org/en/20/core/metadata.html#sqlalchemy.schema.Table)~ Define models using [ORM](https://docs.sqlalchemy.org/en/20/tutorial/metadata.html#using-orm-declarative-forms-to-define-table-metadata).
- [ ] Add parameter : table which is type of Table to the insert, delete, select, update methods in database manager
