Next stage of deprecation cycle for derive_var_afeye() arguments

[manciniedoardo]

Background Information

lat_vals and dataset_occ argument now need to be totally removed as we are in Phase 3 of the deprecation cycle

Note: This issue can be started after the 1.1 release in June 2024

Definition of Done

• lat_vals and dataset_occ argument totally removed from derive_var_afeye() function code
• run devtools::document() to update function documentation
• tests that check for deprecation of these arguments deleted
• NEWS.md updated to say that these arguments have reached the final stage of the deprecation cycle and have now been deleted