Support for delete_all

[mohammednasser-32]

I was wondering if it is intentional that the gem does not support delete_all action, It is the reason behind this bug since has_many_through uses delete_all to delete the related associations.

I was going to work on a PR to add it but I thought it would be better to double check first

Thank you

[mohammednasser-32]

@mathieujobin Hello 👋 can you please let me know if I can proceed with this? Thanks

[mathieujobin]

Yes please proceed.

If you could wrap your changes with a setting and make sure to cover up the feature with tests, that would be most appreciated 👍

Thanks

[mohammednasser-32]

@mathieujobin Done 🙏 PR