Delete lectures of the batch as well when deleting the batch

[bhavyaagg]

[championswimmer]

@bhavyaagg
use paranoid delete
(setting deletedAt on database) instead of hard delete so we retain old information

[bhavyaagg]

@championswimmer Okay sir.

[bhavyaagg]

@championswimmer We have the ability of archiving a batch so should we still add the paranoid delete? By delete i mean an accidentally created batch.